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/ext2fs.h>
43 #include <ext2fs/ext2_types.h>
44 #include <ext2fs/fiemap.h>
45 
46 int verbose = 0;
47 int blocksize;		/* Use specified blocksize (default 1kB) */
48 int sync_file = 0;	/* fsync file before getting the mapping */
49 int xattr_map = 0;	/* get xattr mapping */
50 int force_bmap;	/* force use of FIBMAP instead of FIEMAP */
51 int force_extent;	/* print output in extent format always */
52 int logical_width = 8;
53 int physical_width = 10;
54 const char *ext_fmt = "%4d: %*llu..%*llu: %*llu..%*llu: %6llu: %s\n";
55 const char *hex_fmt = "%4d: %*llx..%*llx: %*llx..%*llx: %6llx: %s\n";
56 
57 #define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
58 
59 #define FIBMAP		_IO(0x00, 1)	/* bmap access */
60 #define FIGETBSZ	_IO(0x00, 2)	/* get the block size used for bmap */
61 
62 #define LUSTRE_SUPER_MAGIC 0x0BD00BD0
63 
64 #define	EXT4_EXTENTS_FL			0x00080000 /* Inode uses extents */
65 #define	EXT3_IOC_GETFLAGS		_IOR('f', 1, long)
66 
int_log2(int arg)67 static int int_log2(int arg)
68 {
69 	int     l = 0;
70 
71 	arg >>= 1;
72 	while (arg) {
73 		l++;
74 		arg >>= 1;
75 	}
76 	return l;
77 }
78 
int_log10(unsigned long long arg)79 static int int_log10(unsigned long long arg)
80 {
81 	int     l = 0;
82 
83 	arg = arg / 10;
84 	while (arg) {
85 		l++;
86 		arg = arg / 10;
87 	}
88 	return l;
89 }
90 
div_ceil(unsigned int a,unsigned int b)91 static unsigned int div_ceil(unsigned int a, unsigned int b)
92 {
93 	if (!a)
94 		return 0;
95 	return ((a - 1) / b) + 1;
96 }
97 
get_bmap(int fd,unsigned long block,unsigned long * phy_blk)98 static int get_bmap(int fd, unsigned long block, unsigned long *phy_blk)
99 {
100 	int	ret;
101 	unsigned int b;
102 
103 	b = block;
104 	ret = ioctl(fd, FIBMAP, &b); /* FIBMAP takes pointer to integer */
105 	if (ret < 0) {
106 		if (errno == EPERM) {
107 			fprintf(stderr, "No permission to use FIBMAP ioctl; "
108 				"must have root privileges\n");
109 		}
110 	}
111 	*phy_blk = b;
112 
113 	return ret;
114 }
115 
print_extent_header(void)116 static void print_extent_header(void)
117 {
118 	printf(" ext: %*s %*s length: %*s flags:\n",
119 	       logical_width * 2 + 3,
120 	       "logical_offset:",
121 	       physical_width * 2 + 3, "physical_offset:",
122 	       physical_width + 1,
123 	       "expected:");
124 }
125 
print_extent_info(struct fiemap_extent * fm_extent,int cur_ex,unsigned long long expected,int blk_shift,ext2fs_struct_stat * st)126 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
127 			      unsigned long long expected, int blk_shift,
128 			      ext2fs_struct_stat *st)
129 {
130 	unsigned long long physical_blk;
131 	unsigned long long logical_blk;
132 	unsigned long long ext_len;
133 	unsigned long long ext_blks;
134 	char flags[256] = "";
135 
136 	/* For inline data all offsets should be in bytes, not blocks */
137 	if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
138 		blk_shift = 0;
139 
140 	ext_len = fm_extent->fe_length >> blk_shift;
141 	ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
142 	logical_blk = fm_extent->fe_logical >> blk_shift;
143 	physical_blk = fm_extent->fe_physical >> blk_shift;
144 
145 	if (expected)
146 		sprintf(flags, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
147 			physical_width, expected >> blk_shift);
148 	else
149 		sprintf(flags, "%.*s  ", physical_width, "                   ");
150 
151 	if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN)
152 		strcat(flags, "unknown,");
153 	if (fm_extent->fe_flags & FIEMAP_EXTENT_DELALLOC)
154 		strcat(flags, "delalloc,");
155 	if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_ENCRYPTED)
156 		strcat(flags, "encrypted,");
157 	if (fm_extent->fe_flags & FIEMAP_EXTENT_NOT_ALIGNED)
158 		strcat(flags, "not_aligned,");
159 	if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
160 		strcat(flags, "inline,");
161 	if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_TAIL)
162 		strcat(flags, "tail_packed,");
163 	if (fm_extent->fe_flags & FIEMAP_EXTENT_UNWRITTEN)
164 		strcat(flags, "unwritten,");
165 	if (fm_extent->fe_flags & FIEMAP_EXTENT_MERGED)
166 		strcat(flags, "merged,");
167 
168 	if (fm_extent->fe_logical + fm_extent->fe_length >= (__u64) st->st_size)
169 		strcat(flags, "eof,");
170 
171 	/* Remove trailing comma, if any */
172 	if (flags[0])
173 		flags[strlen(flags) - 1] = '\0';
174 
175 	printf(ext_fmt, cur_ex, logical_width, logical_blk,
176 	       logical_width, logical_blk + ext_blks,
177 	       physical_width, physical_blk,
178 	       physical_width, physical_blk + ext_blks,
179 	       ext_len, flags);
180 }
181 
filefrag_fiemap(int fd,int blk_shift,int * num_extents,ext2fs_struct_stat * st)182 static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
183 			   ext2fs_struct_stat *st)
184 {
185 	char buf[16384];
186 	struct fiemap *fiemap = (struct fiemap *)buf;
187 	struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
188 	int count = (sizeof(buf) - sizeof(*fiemap)) /
189 			sizeof(struct fiemap_extent);
190 	unsigned long long expected = 0;
191 	unsigned long flags = 0;
192 	unsigned int i;
193 	static int fiemap_incompat_printed;
194 	int fiemap_header_printed = 0;
195 	int tot_extents = 0, n = 0;
196 	int last = 0;
197 	int rc;
198 
199 	memset(fiemap, 0, sizeof(struct fiemap));
200 
201 	if (sync_file)
202 		flags |= FIEMAP_FLAG_SYNC;
203 
204 	if (xattr_map)
205 		flags |= FIEMAP_FLAG_XATTR;
206 
207 	do {
208 		fiemap->fm_length = ~0ULL;
209 		fiemap->fm_flags = flags;
210 		fiemap->fm_extent_count = count;
211 		rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
212 		if (rc < 0) {
213 			if (errno == EBADR && fiemap_incompat_printed == 0) {
214 				printf("FIEMAP failed with unsupported "
215 				       "flags %x\n", fiemap->fm_flags);
216 				fiemap_incompat_printed = 1;
217 			}
218 			return rc;
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 		if (verbose && !fiemap_header_printed) {
226 			print_extent_header();
227 			fiemap_header_printed = 1;
228 		}
229 
230 		for (i = 0; i < fiemap->fm_mapped_extents; i++) {
231 			if (fm_ext[i].fe_logical != 0 &&
232 			    fm_ext[i].fe_physical != expected) {
233 				tot_extents++;
234 			} else {
235 				expected = 0;
236 				if (!tot_extents)
237 					tot_extents = 1;
238 			}
239 			if (verbose)
240 				print_extent_info(&fm_ext[i], n, expected,
241 						  blk_shift, st);
242 
243 			expected = fm_ext[i].fe_physical + fm_ext[i].fe_length;
244 			if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
245 				last = 1;
246 			n++;
247 		}
248 
249 		fiemap->fm_start = (fm_ext[i - 1].fe_logical +
250 				    fm_ext[i - 1].fe_length);
251 	} while (last == 0);
252 
253 	*num_extents = tot_extents;
254 
255 	return 0;
256 }
257 
258 #define EXT2_DIRECT	12
259 
filefrag_fibmap(int fd,int blk_shift,int * num_extents,ext2fs_struct_stat * st,unsigned long numblocks,int is_ext2)260 static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
261 			   ext2fs_struct_stat *st,
262 			   unsigned long numblocks, int is_ext2)
263 {
264 	struct fiemap_extent	fm_ext;
265 	unsigned long		i, last_block;
266 	unsigned long long	logical;
267 				/* Blocks per indirect block */
268 	const long		bpib = st->st_blksize / 4;
269 	int			count;
270 
271 	if (force_extent) {
272 		memset(&fm_ext, 0, sizeof(fm_ext));
273 		fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
274 	}
275 
276 	if (sync_file)
277 		fsync(fd);
278 
279 	for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
280 	     i < numblocks;
281 	     i++, logical += st->st_blksize) {
282 		unsigned long block = 0;
283 		int rc;
284 
285 		if (is_ext2 && last_block) {
286 			if (((i - EXT2_DIRECT) % bpib) == 0)
287 				last_block++;
288 			if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
289 				last_block++;
290 			if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
291 			     (((unsigned long long)bpib) * bpib * bpib)) == 0)
292 				last_block++;
293 		}
294 		rc = get_bmap(fd, i, &block);
295 		if (rc < 0)
296 			return rc;
297 		if (block == 0)
298 			continue;
299 		if (*num_extents == 0) {
300 			(*num_extents)++;
301 			if (force_extent) {
302 				print_extent_header();
303 				fm_ext.fe_physical = block * st->st_blksize;
304 			}
305 		}
306 		count++;
307 		if (force_extent && last_block != 0 &&
308 		    (block != last_block + 1 ||
309 		     fm_ext.fe_logical + fm_ext.fe_length != logical)) {
310 			print_extent_info(&fm_ext, *num_extents - 1,
311 					  (last_block + 1) * st->st_blksize,
312 					  blk_shift, st);
313 			fm_ext.fe_logical = logical;
314 			fm_ext.fe_physical = block * st->st_blksize;
315 			fm_ext.fe_length = 0;
316 			(*num_extents)++;
317 		} else if (verbose && last_block && (block != last_block + 1)) {
318 			printf("Discontinuity: Block %ld is at %lu (was %lu)\n",
319 			       i, block, last_block + 1);
320 			(*num_extents)++;
321 		}
322 		fm_ext.fe_length += st->st_blksize;
323 		last_block = block;
324 	}
325 
326 	if (force_extent)
327 		print_extent_info(&fm_ext, *num_extents - 1,
328 				  last_block * st->st_blksize, blk_shift, st);
329 
330 	return count;
331 }
332 
frag_report(const char * filename)333 static void frag_report(const char *filename)
334 {
335 	static struct statfs fsinfo;
336 	ext2fs_struct_stat st;
337 	int		blk_shift;
338 	long		fd;
339 	unsigned long	numblocks;
340 	int		data_blocks_per_cyl = 1;
341 	int		num_extents = 1, expected = ~0;
342 	int		is_ext2 = 0;
343 	static dev_t	last_device;
344 	unsigned int	flags;
345 	int		width;
346 
347 #if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
348 	fd = open64(filename, O_RDONLY);
349 #else
350 	fd = open(filename, O_RDONLY);
351 #endif
352 	if (fd < 0) {
353 		perror("open");
354 		return;
355 	}
356 
357 #if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
358 	if (fstat64(fd, &st) < 0) {
359 #else
360 	if (fstat(fd, &st) < 0) {
361 #endif
362 		close(fd);
363 		perror("stat");
364 		return;
365 	}
366 
367 	if (last_device != st.st_dev) {
368 		if (fstatfs(fd, &fsinfo) < 0) {
369 			close(fd);
370 			perror("fstatfs");
371 			return;
372 		}
373 		if (verbose)
374 			printf("Filesystem type is: %lx\n",
375 			       (unsigned long) fsinfo.f_type);
376 	}
377 	st.st_blksize = fsinfo.f_bsize;
378 	if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0)
379 		flags = 0;
380 	if (!(flags & EXT4_EXTENTS_FL) &&
381 	    ((fsinfo.f_type == 0xef51) || (fsinfo.f_type == 0xef52) ||
382 	     (fsinfo.f_type == 0xef53)))
383 		is_ext2++;
384 
385 	if (is_ext2) {
386 		long cylgroups = div_ceil(fsinfo.f_blocks, fsinfo.f_bsize * 8);
387 
388 		if (verbose && last_device != st.st_dev)
389 			printf("Filesystem cylinder groups approximately %ld\n",
390 			       cylgroups);
391 
392 		data_blocks_per_cyl = fsinfo.f_bsize * 8 -
393 					(fsinfo.f_files / 8 / cylgroups) - 3;
394 	}
395 	last_device = st.st_dev;
396 
397 	width = int_log10(fsinfo.f_blocks);
398 	if (width > physical_width)
399 		physical_width = width;
400 
401 	numblocks = (st.st_size + fsinfo.f_bsize - 1) / fsinfo.f_bsize;
402 	if (blocksize != 0)
403 		blk_shift = int_log2(blocksize);
404 	else
405 		blk_shift = int_log2(fsinfo.f_bsize);
406 
407 	width = int_log10(numblocks);
408 	if (width > logical_width)
409 		logical_width = width;
410 	if (verbose)
411 		printf("File size of %s is %llu (%lu block%s of %d bytes)\n",
412 		       filename, (unsigned long long)st.st_size,
413 		       numblocks * fsinfo.f_bsize >> blk_shift,
414 		       numblocks == 1 ? "" : "s", 1 << blk_shift);
415 
416 	if (force_bmap ||
417 	    filefrag_fiemap(fd, blk_shift, &num_extents, &st) != 0) {
418 		expected = filefrag_fibmap(fd, blk_shift, &num_extents,
419 					   &st, numblocks, is_ext2);
420 		if (expected < 0) {
421 			if (errno == EINVAL || errno == ENOTTY) {
422 				fprintf(stderr, "%s: FIBMAP unsupported\n",
423 					filename);
424 			} else if (errno != EPERM) {
425 				fprintf(stderr, "%s: FIBMAP error: %s",
426 					filename, strerror(errno));
427 			}
428 			goto out_close;
429 		}
430 		expected = expected / data_blocks_per_cyl + 1;
431 	}
432 
433 	if (num_extents == 1)
434 		printf("%s: 1 extent found", filename);
435 	else
436 		printf("%s: %d extents found", filename, num_extents);
437 	/* count, and thus expected, only set for indirect FIBMAP'd files */
438 	if (is_ext2 && expected && expected < num_extents)
439 		printf(", perfection would be %d extent%s\n", expected,
440 			(expected > 1) ? "s" : "");
441 	else
442 		fputc('\n', stdout);
443 out_close:
444 	close(fd);
445 }
446 
447 static void usage(const char *progname)
448 {
449 	fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeklsvxX] file ...\n",
450 		progname);
451 	exit(1);
452 }
453 
454 int main(int argc, char**argv)
455 {
456 	char **cpp;
457 	int c;
458 
459 	while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF)
460 		switch (c) {
461 		case 'B':
462 			force_bmap++;
463 			break;
464 		case 'b':
465 			if (optarg) {
466 				char *end;
467 				blocksize = strtoul(optarg, &end, 0);
468 				if (end) {
469 					switch (end[0]) {
470 					case 'g':
471 					case 'G':
472 						blocksize *= 1024;
473 						/* no break */
474 					case 'm':
475 					case 'M':
476 						blocksize *= 1024;
477 						/* no break */
478 					case 'k':
479 					case 'K':
480 						blocksize *= 1024;
481 						break;
482 					default:
483 						break;
484 					}
485 				}
486 			} else { /* Allow -b without argument for compat. Remove
487 				  * this eventually so "-b {blocksize}" works */
488 				fprintf(stderr, "%s: -b needs a blocksize "
489 					"option, assuming 1024-byte blocks.\n",
490 					argv[0]);
491 				blocksize = 1024;
492 			}
493 			break;
494 		case 'e':
495 			force_extent++;
496 			if (!verbose)
497 				verbose++;
498 			break;
499 		case 'k':
500 			blocksize = 1024;
501 			break;
502 		case 's':
503 			sync_file++;
504 			break;
505 		case 'v':
506 			verbose++;
507 			break;
508 		case 'x':
509 			xattr_map++;
510 			break;
511 		case 'X':
512 			ext_fmt = hex_fmt;
513 			break;
514 		default:
515 			usage(argv[0]);
516 			break;
517 		}
518 	if (optind == argc)
519 		usage(argv[0]);
520 	for (cpp=argv+optind; *cpp; cpp++)
521 		frag_report(*cpp);
522 	return 0;
523 }
524 #endif
525