filefrag.c revision 00eb0eee0addfd3b7ede98b85e00dff1547838a0
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#include "config.h" 13#ifndef __linux__ 14#include <stdio.h> 15#include <stdlib.h> 16#include <unistd.h> 17 18int main(void) { 19 fputs("This program is only supported on Linux!\n", stderr); 20 exit(EXIT_FAILURE); 21} 22#else 23#define _LARGEFILE64_SOURCE 24 25#include <stdio.h> 26#include <stdlib.h> 27#include <unistd.h> 28#include <string.h> 29#include <time.h> 30#include <fcntl.h> 31#include <errno.h> 32#ifdef HAVE_GETOPT_H 33#include <getopt.h> 34#else 35extern char *optarg; 36extern int optind; 37#endif 38#include <sys/types.h> 39#include <sys/stat.h> 40#include <sys/vfs.h> 41#include <sys/ioctl.h> 42#include <linux/fd.h> 43#include <ext2fs/ext2_types.h> 44#include <ext2fs/fiemap.h> 45 46int verbose = 0; 47int no_bs = 0; /* Don't use the files blocksize, use 1K blocksize */ 48int sync_file = 0; /* fsync file before getting the mapping */ 49int xattr_map = 0; /* get xattr mapping */ 50int force_bmap = 0; 51int logical_width = 12; 52int physical_width = 14; 53unsigned long long filesize; 54 55#define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR) 56 57#define FIBMAP _IO(0x00, 1) /* bmap access */ 58#define FIGETBSZ _IO(0x00, 2) /* get the block size used for bmap */ 59 60#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */ 61#define EXT3_IOC_GETFLAGS _IOR('f', 1, long) 62 63static 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 75static 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 87static 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 94static 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 114static 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 166static 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 expected = 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 = 0, n = 0; 179 int last = 0; 180 int rc; 181 182 memset(fiemap, 0, sizeof(struct fiemap)); 183 184 if (sync_file) 185 flags |= FIEMAP_FLAG_SYNC; 186 187 if (xattr_map) 188 flags |= FIEMAP_FLAG_XATTR; 189 190 do { 191 fiemap->fm_length = ~0ULL; 192 fiemap->fm_flags = flags; 193 fiemap->fm_extent_count = count; 194 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap); 195 if (rc < 0) { 196 if (errno == EBADR && fiemap_incompat_printed == 0) { 197 printf("FIEMAP failed with unsupported " 198 "flags %x\n", fiemap->fm_flags); 199 fiemap_incompat_printed = 1; 200 } 201 return rc; 202 } 203 204 /* If 0 extents are returned, then more ioctls are not needed */ 205 if (fiemap->fm_mapped_extents == 0) 206 break; 207 208 if (verbose && !fiemap_header_printed) { 209 printf(" ext %*s %*s %*s length flags\n", logical_width, 210 "logical", physical_width, "physical", 211 physical_width, "expected"); 212 fiemap_header_printed = 1; 213 } 214 215 for (i = 0; i < fiemap->fm_mapped_extents; i++) { 216 __u64 phy_blk, logical_blk; 217 unsigned long ext_len; 218 219 phy_blk = fm_ext[i].fe_physical >> blk_shift; 220 ext_len = fm_ext[i].fe_length >> blk_shift; 221 logical_blk = fm_ext[i].fe_logical >> blk_shift; 222 223 if (logical_blk && phy_blk != expected) { 224 tot_extents++; 225 } else { 226 expected = 0; 227 if (!tot_extents) 228 tot_extents = 1; 229 } 230 if (verbose) 231 print_extent_info(&fm_ext[i], n, expected, 232 blk_shift); 233 234 expected = phy_blk + ext_len; 235 if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST) 236 last = 1; 237 n++; 238 } 239 240 fiemap->fm_start = (fm_ext[i-1].fe_logical + 241 fm_ext[i-1].fe_length); 242 } while (last == 0); 243 244 *num_extents = tot_extents; 245 246 return 0; 247} 248 249#define EXT2_DIRECT 12 250 251static void frag_report(const char *filename) 252{ 253 struct statfs fsinfo; 254#ifdef HAVE_FSTAT64 255 struct stat64 fileinfo; 256#else 257 struct stat fileinfo; 258#endif 259 int bs; 260 long fd; 261 unsigned long block, last_block = 0, numblocks, i, count = 0; 262 long bpib; /* Blocks per indirect block */ 263 long cylgroups; 264 int num_extents = 0, expected; 265 int is_ext2 = 0; 266 static int once = 1; 267 unsigned int flags; 268 int rc; 269 270#ifdef HAVE_OPEN64 271 fd = open64(filename, O_RDONLY); 272#else 273 fd = open(filename, O_RDONLY); 274#endif 275 if (fd < 0) { 276 perror("open"); 277 return; 278 } 279 280 if (statfs(filename, &fsinfo) < 0) { 281 perror("statfs"); 282 return; 283 } 284#ifdef HAVE_FSTAT64 285 if (stat64(filename, &fileinfo) < 0) { 286#else 287 if (stat(filename, &fileinfo) < 0) { 288#endif 289 perror("stat"); 290 return; 291 } 292 if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0) 293 flags = 0; 294 if (!(flags & EXT4_EXTENTS_FL) && 295 ((fsinfo.f_type == 0xef51) || (fsinfo.f_type == 0xef52) || 296 (fsinfo.f_type == 0xef53))) 297 is_ext2++; 298 if (verbose && once) 299 printf("Filesystem type is: %lx\n", 300 (unsigned long) fsinfo.f_type); 301 302 cylgroups = div_ceil(fsinfo.f_blocks, fsinfo.f_bsize*8); 303 if (verbose && is_ext2 && once) 304 printf("Filesystem cylinder groups is approximately %ld\n", 305 cylgroups); 306 307 physical_width = int_log10(fsinfo.f_blocks); 308 if (physical_width < 8) 309 physical_width = 8; 310 311 if (ioctl(fd, FIGETBSZ, &bs) < 0) { /* FIGETBSZ takes an int */ 312 perror("FIGETBSZ"); 313 close(fd); 314 return; 315 } 316 317 if (no_bs) 318 bs = 1024; 319 320 bpib = bs / 4; 321 numblocks = (fileinfo.st_size + (bs-1)) / bs; 322 logical_width = int_log10(numblocks); 323 if (logical_width < 7) 324 logical_width = 7; 325 filesize = (long long)fileinfo.st_size; 326 if (verbose) 327 printf("File size of %s is %lld (%ld block%s, blocksize %d)\n", 328 filename, (long long) fileinfo.st_size, numblocks, 329 numblocks == 1 ? "" : "s", bs); 330 if (force_bmap || 331 filefrag_fiemap(fd, int_log2(bs), &num_extents) != 0) { 332 for (i = 0, count = 0; i < numblocks; i++) { 333 if (is_ext2 && last_block) { 334 if (((i-EXT2_DIRECT) % bpib) == 0) 335 last_block++; 336 if (((i-EXT2_DIRECT-bpib) % (bpib*bpib)) == 0) 337 last_block++; 338 if (((i-EXT2_DIRECT-bpib-bpib*bpib) % 339 (((__u64) bpib)*bpib*bpib)) == 0) 340 last_block++; 341 } 342 rc = get_bmap(fd, i, &block); 343 if (block == 0) 344 continue; 345 if (!num_extents) 346 num_extents++; 347 count++; 348 if (last_block && (block != last_block+1) ) { 349 if (verbose) 350 printf("Discontinuity: Block %ld is at " 351 "%lu (was %lu)\n", 352 i, block, last_block+1); 353 num_extents++; 354 } 355 last_block = block; 356 } 357 } 358 if (num_extents == 1) 359 printf("%s: 1 extent found", filename); 360 else 361 printf("%s: %d extents found", filename, num_extents); 362 /* count, and thus expected, only set for indirect FIBMAP'd files */ 363 if (is_ext2) { 364 expected = (count/((bs*8)-(fsinfo.f_files/8/cylgroups)-3))+1; 365 if (expected && expected < num_extents) 366 printf(", perfection would be %d extent%s\n", expected, 367 (expected>1) ? "s" : ""); 368 } else 369 fputc('\n', stdout); 370 close(fd); 371 once = 0; 372} 373 374static void usage(const char *progname) 375{ 376 fprintf(stderr, "Usage: %s [-Bbvsx] file ...\n", progname); 377 exit(1); 378} 379 380int main(int argc, char**argv) 381{ 382 char **cpp; 383 int c; 384 385 while ((c = getopt(argc, argv, "Bbsvx")) != EOF) 386 switch (c) { 387 case 'B': 388 force_bmap++; 389 break; 390 case 'b': 391 no_bs++; 392 break; 393 case 'v': 394 verbose++; 395 break; 396 case 's': 397 sync_file++; 398 break; 399 case 'x': 400 xattr_map++; 401 break; 402 default: 403 usage(argv[0]); 404 break; 405 } 406 if (optind == argc) 407 usage(argv[0]); 408 for (cpp=argv+optind; *cpp; cpp++) 409 frag_report(*cpp); 410 return 0; 411} 412#endif 413