mke2fs.c revision 1.9.2.1 1 /* $NetBSD: mke2fs.c,v 1.9.2.1 2011/01/16 12:38:27 bouyer Exp $ */
2
3 /*-
4 * Copyright (c) 2007 Izumi Tsutsui. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 /*
28 * Copyright (c) 1980, 1989, 1993
29 * The Regents of the University of California. All rights reserved.
30 *
31 * Redistribution and use in source and binary forms, with or without
32 * modification, are permitted provided that the following conditions
33 * are met:
34 * 1. Redistributions of source code must retain the above copyright
35 * notice, this list of conditions and the following disclaimer.
36 * 2. Redistributions in binary form must reproduce the above copyright
37 * notice, this list of conditions and the following disclaimer in the
38 * documentation and/or other materials provided with the distribution.
39 * 3. Neither the name of the University nor the names of its contributors
40 * may be used to endorse or promote products derived from this software
41 * without specific prior written permission.
42 *
43 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
44 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
47 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * SUCH DAMAGE.
54 */
55
56 /*
57 * Copyright (c) 1997 Manuel Bouyer.
58 *
59 * Redistribution and use in source and binary forms, with or without
60 * modification, are permitted provided that the following conditions
61 * are met:
62 * 1. Redistributions of source code must retain the above copyright
63 * notice, this list of conditions and the following disclaimer.
64 * 2. Redistributions in binary form must reproduce the above copyright
65 * notice, this list of conditions and the following disclaimer in the
66 * documentation and/or other materials provided with the distribution.
67 * 3. All advertising materials mentioning features or use of this software
68 * must display the following acknowledgement:
69 * This product includes software developed by Manuel Bouyer.
70 * 4. The name of the author may not be used to endorse or promote products
71 * derived from this software without specific prior written permission.
72 *
73 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
74 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
75 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
76 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
77 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
78 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
79 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
80 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
81 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
82 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
83 */
84
85 /*
86 * mke2fs.c: "re-invent (dumb but non-GPLed) wheel as a fun project"
87 *
88 * In spite of this name, there is no piece of code
89 * derived from GPLed e2fsprogs written for Linux.
90 * I referred them only to see how each structure
91 * member should be initialized.
92 *
93 * Reference:
94 * - All NetBSD sources under src/sys/ufs/ext2fs and src/sbin/fsck_ext2fs
95 * - Ext2fs Home Page
96 * http://e2fsprogs.sourceforge.net/ext2.html
97 * - Design and Implementation of the Second Extended Filesystem
98 * http://e2fsprogs.sourceforge.net/ext2intro.html
99 * - Linux Documentation "The Second Extended Filesystem"
100 * src/linux/Documentation/filesystems/ext2.txt
101 * in the Linux kernel distribution
102 */
103
104 #include <sys/cdefs.h>
105 #ifndef lint
106 #if 0
107 static char sccsid[] = "@(#)mkfs.c 8.11 (Berkeley) 5/3/95";
108 #else
109 __RCSID("$NetBSD: mke2fs.c,v 1.9.2.1 2011/01/16 12:38:27 bouyer Exp $");
110 #endif
111 #endif /* not lint */
112
113 #include <sys/param.h>
114 #include <sys/mman.h>
115 #include <sys/time.h>
116 #include <ufs/ext2fs/ext2fs_dinode.h>
117 #include <ufs/ext2fs/ext2fs_dir.h>
118 #include <ufs/ext2fs/ext2fs.h>
119 #include <sys/ioctl.h>
120
121 #include <err.h>
122 #include <errno.h>
123 #include <string.h>
124 #include <unistd.h>
125 #include <stdlib.h>
126 #include <stddef.h>
127 #include <stdio.h>
128 #include <uuid.h>
129
130 #include "extern.h"
131
132 static void initcg(uint);
133 static void zap_old_sblock(daddr_t);
134 static uint cgoverhead(uint);
135 static int fsinit(const struct timeval *);
136 static int makedir(struct ext2fs_direct *, int);
137 static void copy_dir(struct ext2fs_direct *, struct ext2fs_direct *);
138 static void init_resizeino(const struct timeval *);
139 static uint32_t alloc(uint32_t, uint16_t);
140 static void iput(struct ext2fs_dinode *, ino_t);
141 static void rdfs(daddr_t, int, void *);
142 static void wtfs(daddr_t, int, void *);
143 static int ilog2(uint);
144 static int skpc(int, size_t, uint8_t *);
145
146 /* XXX: some of these macro should be into <ufs/ext2fs/ext2fs.h>? */
147 #define EXT2_DEF_MAX_MNT_COUNT 20
148 #define EXT2_DEF_FSCKINTV (180 * 24 * 60 * 60) /* 180 days */
149 #define EXT2_RESERVED_INODES (EXT2_FIRSTINO - 1)
150 #define EXT2_UMASK 0755
151
152 #define EXT2_INO_INDEX(ino) ((ino) - 1) /* no inode zero */
153
154 #define EXT2_LOSTFOUNDSIZE 16384
155 #define EXT2_LOSTFOUNDINO EXT2_FIRSTINO /* XXX: not quite */
156 #define EXT2_LOSTFOUNDUMASK 0700
157
158 #define EXT2_RESIZEINOUMASK 0600
159
160 #define NBLOCK_SUPERBLOCK 1
161 #define NBLOCK_BLOCK_BITMAP 1
162 #define NBLOCK_INODE_BITMAP 1
163
164 #define cgbase(fs, c) \
165 ((fs)->e2fs.e2fs_first_dblock + (fs)->e2fs.e2fs_bpg * (c))
166
167
168 /*
169 * ext2fs super block and group descriptor structures
170 *
171 * We don't have to use or setup whole in-memory m_ext2fs structure,
172 * but prepare it to use several macro defined in kernel headers.
173 */
174 union {
175 struct m_ext2fs m_ext2fs;
176 char pad[SBSIZE];
177 } ext2fsun;
178 #define sblock ext2fsun.m_ext2fs
179 #define gd ext2fsun.m_ext2fs.e2fs_gd
180
181 static uint8_t *iobuf; /* for superblock and group descriptors */
182 static int iobufsize;
183
184 static uint8_t buf[MAXBSIZE]; /* for initcg() and makedir() ops */
185
186 static int fsi, fso;
187
188 void
189 mke2fs(const char *fsys, int fi, int fo)
190 {
191 struct timeval tv;
192 int64_t minfssize;
193 uint bcount, fbcount, ficount;
194 uint blocks_gd, blocks_per_cg, inodes_per_cg, iblocks_per_cg;
195 uint minblocks_per_cg, blocks_lastcg;
196 uint ncg, cylno, sboff;
197 uuid_t uuid;
198 uint32_t uustat;
199 int i, len, col, delta, fld_width, max_cols;
200 struct winsize winsize;
201
202 gettimeofday(&tv, NULL);
203 fsi = fi;
204 fso = fo;
205
206 /*
207 * collect and verify the block and fragment sizes
208 */
209 if (!powerof2(bsize)) {
210 errx(EXIT_FAILURE,
211 "block size must be a power of 2, not %u\n",
212 bsize);
213 }
214 if (!powerof2(fsize)) {
215 errx(EXIT_FAILURE,
216 "fragment size must be a power of 2, not %u\n",
217 fsize);
218 }
219 if (fsize < sectorsize) {
220 errx(EXIT_FAILURE,
221 "fragment size %u is too small, minimum is %u\n",
222 fsize, sectorsize);
223 }
224 if (bsize < MINBSIZE) {
225 errx(EXIT_FAILURE,
226 "block size %u is too small, minimum is %u\n",
227 bsize, MINBSIZE);
228 }
229 if (bsize > EXT2_MAXBSIZE) {
230 errx(EXIT_FAILURE,
231 "block size %u is too large, maximum is %u\n",
232 bsize, MAXBSIZE);
233 }
234 if (bsize != fsize) {
235 /*
236 * There is no fragment support on current ext2fs (yet?),
237 * but some kernel code refers fsize or fpg as bsize or bpg
238 * and Linux seems to set the same values to them.
239 */
240 errx(EXIT_FAILURE,
241 "block size (%u) can't be different from "
242 "fragment size (%u)\n",
243 bsize, fsize);
244 }
245
246 /* variable inodesize is REV1 feature */
247 if (Oflag == 0 && inodesize != EXT2_REV0_DINODE_SIZE) {
248 errx(EXIT_FAILURE, "GOOD_OLD_REV file system format"
249 " doesn't support %d byte inode\n", inodesize);
250 }
251
252 sblock.e2fs.e2fs_log_bsize = ilog2(bsize) - LOG_MINBSIZE;
253 /* Umm, why not e2fs_log_fsize? */
254 sblock.e2fs.e2fs_fsize = ilog2(fsize) - LOG_MINBSIZE;
255
256 sblock.e2fs_bsize = bsize;
257 sblock.e2fs_bshift = sblock.e2fs.e2fs_log_bsize + LOG_MINBSIZE;
258 sblock.e2fs_qbmask = sblock.e2fs_bsize - 1;
259 sblock.e2fs_bmask = ~sblock.e2fs_qbmask;
260 sblock.e2fs_fsbtodb = ilog2(sblock.e2fs_bsize) - ilog2(sectorsize);
261 sblock.e2fs_ipb = sblock.e2fs_bsize / inodesize;
262
263 /*
264 * Ext2fs preserves BBSIZE (1024 bytes) space at the top for
265 * bootloader (though it is not enough at all for our bootloader).
266 * If bsize == BBSIZE we have to preserve one block.
267 * If bsize > BBSIZE, the first block already contains BBSIZE space
268 * before superblock because superblock is allocated at SBOFF and
269 * bsize is a power of two (i.e. 2048 bytes or more).
270 */
271 sblock.e2fs.e2fs_first_dblock = (sblock.e2fs_bsize > BBSIZE) ? 0 : 1;
272 minfssize = fsbtodb(&sblock,
273 sblock.e2fs.e2fs_first_dblock +
274 NBLOCK_SUPERBLOCK +
275 1 /* at least one group descriptor */ +
276 NBLOCK_BLOCK_BITMAP +
277 NBLOCK_INODE_BITMAP +
278 1 /* at least one inode table block */ +
279 1 /* at least one data block for rootdir */ +
280 1 /* at least one data block for data */
281 ); /* XXX and more? */
282
283 if (fssize < minfssize)
284 errx(EXIT_FAILURE, "Filesystem size %" PRId64
285 " < minimum size of %" PRId64 "\n", fssize, minfssize);
286
287 bcount = dbtofsb(&sblock, fssize);
288
289 /*
290 * While many people claim that ext2fs is a (bad) clone of ufs/ffs,
291 * it isn't actual ffs so maybe we should call it "block group"
292 * as their native name rather than ffs derived "cylinder group."
293 * But we'll use the latter here since other kernel sources use it.
294 * (I also agree "cylinder" based allocation is obsolete though)
295 */
296
297 /* maybe "simple is the best" */
298 blocks_per_cg = sblock.e2fs_bsize * NBBY;
299
300 ncg = howmany(bcount - sblock.e2fs.e2fs_first_dblock, blocks_per_cg);
301 blocks_gd = howmany(sizeof(struct ext2_gd) * ncg, bsize);
302
303 /* check range of inode number */
304 if (num_inodes < EXT2_FIRSTINO)
305 num_inodes = EXT2_FIRSTINO; /* needs reserved inodes + 1 */
306 if (num_inodes > UINT16_MAX * ncg)
307 num_inodes = UINT16_MAX * ncg; /* ext2bgd_nifree is uint16_t */
308
309 inodes_per_cg = num_inodes / ncg;
310 iblocks_per_cg = howmany(inodesize * inodes_per_cg, bsize);
311
312 /* Check that the last cylinder group has enough space for inodes */
313 minblocks_per_cg =
314 NBLOCK_BLOCK_BITMAP +
315 NBLOCK_INODE_BITMAP +
316 iblocks_per_cg +
317 1; /* at least one data block */
318 if (Oflag == 0 || cg_has_sb(ncg - 1) != 0)
319 minblocks_per_cg += NBLOCK_SUPERBLOCK + blocks_gd;
320
321 blocks_lastcg = bcount - sblock.e2fs.e2fs_first_dblock -
322 blocks_per_cg * (ncg - 1);
323 if (blocks_lastcg < minblocks_per_cg) {
324 /*
325 * Since we make all the cylinder groups the same size, the
326 * last will only be small if there are more than one
327 * cylinder groups. If the last one is too small to store
328 * filesystem data, just kill it.
329 *
330 * XXX: Does fsck_ext2fs(8) properly handle this case?
331 */
332 bcount -= blocks_lastcg;
333 ncg--;
334 blocks_lastcg = blocks_per_cg;
335 blocks_gd = howmany(sizeof(struct ext2_gd) * ncg, bsize);
336 inodes_per_cg = num_inodes / ncg;
337 }
338 /* roundup inodes_per_cg to make it use whole inode table blocks */
339 inodes_per_cg = roundup(inodes_per_cg, sblock.e2fs_ipb);
340 num_inodes = inodes_per_cg * ncg;
341 iblocks_per_cg = inodes_per_cg / sblock.e2fs_ipb;
342
343 /* XXX: probably we should check these adjusted values again */
344
345 sblock.e2fs.e2fs_bcount = bcount;
346 sblock.e2fs.e2fs_icount = num_inodes;
347
348 sblock.e2fs_ncg = ncg;
349 sblock.e2fs_ngdb = blocks_gd;
350 sblock.e2fs_itpg = iblocks_per_cg;
351
352 sblock.e2fs.e2fs_rbcount = sblock.e2fs.e2fs_bcount * minfree / 100;
353 /* e2fs_fbcount will be accounted later */
354 /* e2fs_ficount will be accounted later */
355
356 sblock.e2fs.e2fs_bpg = blocks_per_cg;
357 sblock.e2fs.e2fs_fpg = blocks_per_cg;
358
359 sblock.e2fs.e2fs_ipg = inodes_per_cg;
360
361 sblock.e2fs.e2fs_mtime = 0;
362 sblock.e2fs.e2fs_wtime = tv.tv_sec;
363 sblock.e2fs.e2fs_mnt_count = 0;
364 /* XXX: should add some entropy to avoid checking all fs at once? */
365 sblock.e2fs.e2fs_max_mnt_count = EXT2_DEF_MAX_MNT_COUNT;
366
367 sblock.e2fs.e2fs_magic = E2FS_MAGIC;
368 sblock.e2fs.e2fs_state = E2FS_ISCLEAN;
369 sblock.e2fs.e2fs_beh = E2FS_BEH_DEFAULT;
370 sblock.e2fs.e2fs_minrev = 0;
371 sblock.e2fs.e2fs_lastfsck = tv.tv_sec;
372 sblock.e2fs.e2fs_fsckintv = EXT2_DEF_FSCKINTV;
373
374 /*
375 * Maybe we can use E2FS_OS_FREEBSD here and it would be more proper,
376 * but the purpose of this newfs_ext2fs(8) command is to provide
377 * a filesystem which can be recognized by firmware on some
378 * Linux based appliances that can load bootstrap files only from
379 * (their native) ext2fs, and anyway we will (and should) try to
380 * act like them as much as possible.
381 *
382 * Anyway, I hope that all newer such boxes will keep their support
383 * for the "GOOD_OLD_REV" ext2fs.
384 */
385 sblock.e2fs.e2fs_creator = E2FS_OS_LINUX;
386
387 if (Oflag == 0) {
388 sblock.e2fs.e2fs_rev = E2FS_REV0;
389 sblock.e2fs.e2fs_features_compat = 0;
390 sblock.e2fs.e2fs_features_incompat = 0;
391 sblock.e2fs.e2fs_features_rocompat = 0;
392 } else {
393 sblock.e2fs.e2fs_rev = E2FS_REV1;
394 /*
395 * e2fsprogs say "REV1" is "dynamic" so
396 * it isn't quite a version and maybe it means
397 * "extended from REV0 so check compat features."
398 *
399 * XXX: We don't have any native tool to activate
400 * the EXT2F_COMPAT_RESIZE feature and
401 * fsck_ext2fs(8) might not fix structures for it.
402 */
403 sblock.e2fs.e2fs_features_compat = EXT2F_COMPAT_RESIZE;
404 sblock.e2fs.e2fs_features_incompat = EXT2F_INCOMPAT_FTYPE;
405 sblock.e2fs.e2fs_features_rocompat =
406 EXT2F_ROCOMPAT_SPARSESUPER | EXT2F_ROCOMPAT_LARGEFILE;
407 }
408
409 sblock.e2fs.e2fs_ruid = geteuid();
410 sblock.e2fs.e2fs_rgid = getegid();
411
412 sblock.e2fs.e2fs_first_ino = EXT2_FIRSTINO;
413 sblock.e2fs.e2fs_inode_size = inodesize;
414
415 /* e2fs_block_group_nr is set on writing superblock to each group */
416
417 uuid_create(&uuid, &uustat);
418 if (uustat != uuid_s_ok)
419 errx(EXIT_FAILURE, "Failed to generate uuid\n");
420 uuid_enc_le(sblock.e2fs.e2fs_uuid, &uuid);
421 if (volname != NULL) {
422 if (strlen(volname) > sizeof(sblock.e2fs.e2fs_vname))
423 errx(EXIT_FAILURE, "Volume name is too long");
424 strlcpy(sblock.e2fs.e2fs_vname, volname,
425 sizeof(sblock.e2fs.e2fs_vname));
426 }
427
428 sblock.e2fs.e2fs_fsmnt[0] = '\0';
429 sblock.e2fs_fsmnt[0] = '\0';
430
431 sblock.e2fs.e2fs_algo = 0; /* XXX unsupported? */
432 sblock.e2fs.e2fs_prealloc = 0; /* XXX unsupported? */
433 sblock.e2fs.e2fs_dir_prealloc = 0; /* XXX unsupported? */
434
435 /* calculate blocks for reserved group descriptors for resize */
436 sblock.e2fs.e2fs_reserved_ngdb = 0;
437 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
438 (sblock.e2fs.e2fs_features_compat & EXT2F_COMPAT_RESIZE) != 0) {
439 uint64_t target_blocks;
440 uint target_ncg, target_ngdb, reserved_ngdb;
441
442 /* reserve descriptors for size as 1024 times as current */
443 target_blocks =
444 (sblock.e2fs.e2fs_bcount - sblock.e2fs.e2fs_first_dblock)
445 * 1024ULL;
446 /* number of blocks must be in uint32_t */
447 if (target_blocks > UINT32_MAX)
448 target_blocks = UINT32_MAX;
449 target_ncg = howmany(target_blocks, sblock.e2fs.e2fs_bpg);
450 target_ngdb = howmany(sizeof(struct ext2_gd) * target_ncg,
451 sblock.e2fs_bsize);
452 /*
453 * Reserved group descriptor blocks are preserved as
454 * the second level double indirect reference blocks in
455 * the EXT2_RESIZEINO inode, so the maximum number of
456 * the blocks is NINDIR(fs).
457 * (see also descriptions in init_resizeino() function)
458 *
459 * We check a number including current e2fs_ngdb here
460 * because they will be moved into reserved gdb on
461 * possible future size shrink, though e2fsprogs don't
462 * seem to care about it.
463 */
464 if (target_ngdb > NINDIR(&sblock))
465 target_ngdb = NINDIR(&sblock);
466
467 reserved_ngdb = target_ngdb - sblock.e2fs_ngdb;
468
469 /* make sure reserved_ngdb fits in the last cg */
470 if (reserved_ngdb >= blocks_lastcg - cgoverhead(ncg - 1))
471 reserved_ngdb = blocks_lastcg - cgoverhead(ncg - 1);
472 if (reserved_ngdb == 0) {
473 /* if no space for reserved gdb, disable the feature */
474 sblock.e2fs.e2fs_features_compat &=
475 ~EXT2F_COMPAT_RESIZE;
476 }
477 sblock.e2fs.e2fs_reserved_ngdb = reserved_ngdb;
478 }
479
480 /*
481 * Initialize group descriptors
482 */
483 gd = malloc(sblock.e2fs_ngdb * bsize);
484 if (gd == NULL)
485 errx(EXIT_FAILURE, "Can't allocate descriptors buffer");
486 memset(gd, 0, sblock.e2fs_ngdb * bsize);
487
488 fbcount = 0;
489 ficount = 0;
490 for (cylno = 0; cylno < ncg; cylno++) {
491 uint boffset;
492
493 boffset = cgbase(&sblock, cylno);
494 if (sblock.e2fs.e2fs_rev == E2FS_REV0 ||
495 (sblock.e2fs.e2fs_features_rocompat &
496 EXT2F_ROCOMPAT_SPARSESUPER) == 0 ||
497 cg_has_sb(cylno)) {
498 boffset += NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb;
499 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
500 (sblock.e2fs.e2fs_features_compat &
501 EXT2F_COMPAT_RESIZE) != 0)
502 boffset += sblock.e2fs.e2fs_reserved_ngdb;
503 }
504 gd[cylno].ext2bgd_b_bitmap = boffset;
505 boffset += NBLOCK_BLOCK_BITMAP;
506 gd[cylno].ext2bgd_i_bitmap = boffset;
507 boffset += NBLOCK_INODE_BITMAP;
508 gd[cylno].ext2bgd_i_tables = boffset;
509 if (cylno == (ncg - 1))
510 gd[cylno].ext2bgd_nbfree =
511 blocks_lastcg - cgoverhead(cylno);
512 else
513 gd[cylno].ext2bgd_nbfree =
514 sblock.e2fs.e2fs_bpg - cgoverhead(cylno);
515 fbcount += gd[cylno].ext2bgd_nbfree;
516 gd[cylno].ext2bgd_nifree = sblock.e2fs.e2fs_ipg;
517 if (cylno == 0) {
518 /* take reserved inodes off nifree */
519 gd[cylno].ext2bgd_nifree -= EXT2_RESERVED_INODES;
520 }
521 ficount += gd[cylno].ext2bgd_nifree;
522 gd[cylno].ext2bgd_ndirs = 0;
523 }
524 sblock.e2fs.e2fs_fbcount = fbcount;
525 sblock.e2fs.e2fs_ficount = ficount;
526
527 /*
528 * Dump out summary information about file system.
529 */
530 if (verbosity > 0) {
531 printf("%s: %u.%1uMB (%" PRId64 " sectors) "
532 "block size %u, fragment size %u\n",
533 fsys,
534 (uint)(((uint64_t)bcount * bsize) / (1024 * 1024)),
535 (uint)((uint64_t)bcount * bsize -
536 rounddown((uint64_t)bcount * bsize, 1024 * 1024))
537 / 1024 / 100,
538 fssize, bsize, fsize);
539 printf("\tusing %u block groups of %u.0MB, %u blks, "
540 "%u inodes.\n",
541 ncg, bsize * sblock.e2fs.e2fs_bpg / (1024 * 1024),
542 sblock.e2fs.e2fs_bpg, sblock.e2fs.e2fs_ipg);
543 }
544
545 /*
546 * allocate space for superblock and group descriptors
547 */
548 iobufsize = (NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb) * sblock.e2fs_bsize;
549 iobuf = mmap(0, iobufsize, PROT_READ|PROT_WRITE,
550 MAP_ANON|MAP_PRIVATE, -1, 0);
551 if (iobuf == NULL)
552 errx(EXIT_FAILURE, "Cannot allocate I/O buffer\n");
553 memset(iobuf, 0, iobufsize);
554
555 /*
556 * We now start writing to the filesystem
557 */
558
559 if (!Nflag) {
560 static const uint pbsize[] = { 1024, 2048, 4096, 0 };
561 uint pblock, epblock;
562 /*
563 * Validate the given file system size.
564 * Verify that its last block can actually be accessed.
565 * Convert to file system fragment sized units.
566 */
567 if (fssize <= 0)
568 errx(EXIT_FAILURE, "Preposterous size %" PRId64 "\n",
569 fssize);
570 wtfs(fssize - 1, sectorsize, iobuf);
571
572 /*
573 * Ensure there is nothing that looks like a filesystem
574 * superblock anywhere other than where ours will be.
575 * If fsck_ext2fs finds the wrong one all hell breaks loose!
576 *
577 * XXX: needs to check how fsck_ext2fs programs even
578 * on other OSes determine alternate superblocks
579 */
580 for (i = 0; pbsize[i] != 0; i++) {
581 epblock = (uint64_t)bcount * bsize / pbsize[i];
582 for (pblock = ((pbsize[i] == SBSIZE) ? 1 : 0);
583 pblock < epblock;
584 pblock += pbsize[i] * NBBY /* bpg */)
585 zap_old_sblock((daddr_t)pblock *
586 pbsize[i] / sectorsize);
587 }
588 }
589
590 if (verbosity >= 3)
591 printf("super-block backups (for fsck_ext2fs -b #) at:\n");
592 /* If we are printing more than one line of numbers, line up columns */
593 fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64,
594 (uint64_t)cgbase(&sblock, ncg - 1));
595 /* Get terminal width */
596 if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0)
597 max_cols = winsize.ws_col;
598 else
599 max_cols = 80;
600 if (Nflag && verbosity == 3)
601 /* Leave space to add " ..." after one row of numbers */
602 max_cols -= 4;
603 #define BASE 0x10000 /* For some fixed-point maths */
604 col = 0;
605 delta = verbosity > 2 ? 0 : max_cols * BASE / ncg;
606 for (cylno = 0; cylno < ncg; cylno++) {
607 fflush(stdout);
608 initcg(cylno);
609 if (verbosity < 2)
610 continue;
611 /* the first one is a master, not backup */
612 if (cylno == 0)
613 continue;
614 /* skip if this cylinder doesn't have a backup */
615 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
616 (sblock.e2fs.e2fs_features_rocompat &
617 EXT2F_ROCOMPAT_SPARSESUPER) != 0 &&
618 cg_has_sb(cylno) == 0)
619 continue;
620
621 if (delta > 0) {
622 if (Nflag)
623 /* No point doing dots for -N */
624 break;
625 /* Print dots scaled to end near RH margin */
626 for (col += delta; col > BASE; col -= BASE)
627 printf(".");
628 continue;
629 }
630 /* Print superblock numbers */
631 len = printf(" %*" PRIu64 "," + !col, fld_width,
632 (uint64_t)cgbase(&sblock, cylno));
633 col += len;
634 if (col + len < max_cols)
635 /* Next number fits */
636 continue;
637 /* Next number won't fit, need a newline */
638 if (verbosity <= 3) {
639 /* Print dots for subsequent cylinder groups */
640 delta = sblock.e2fs_ncg - cylno - 1;
641 if (delta != 0) {
642 if (Nflag) {
643 printf(" ...");
644 break;
645 }
646 delta = max_cols * BASE / delta;
647 }
648 }
649 col = 0;
650 printf("\n");
651 }
652 #undef BASE
653 if (col > 0)
654 printf("\n");
655 if (Nflag)
656 return;
657
658 /*
659 * Now construct the initial file system,
660 */
661 if (fsinit(&tv) == 0)
662 errx(EXIT_FAILURE, "Error making filesystem");
663 /*
664 * Write out the superblock and group descriptors
665 */
666 sblock.e2fs.e2fs_block_group_nr = 0;
667 sboff = 0;
668 if (cgbase(&sblock, 0) == 0) {
669 /*
670 * If the first block contains the boot block sectors,
671 * (i.e. in case of sblock.e2fs.e2fs_bsize > BBSIZE)
672 * we have to preserve data in it.
673 */
674 sboff = SBOFF;
675 }
676 e2fs_sbsave(&sblock.e2fs, (struct ext2fs *)(iobuf + sboff));
677 e2fs_cgsave(gd, (struct ext2_gd *)(iobuf + sblock.e2fs_bsize),
678 sizeof(struct ext2_gd) * sblock.e2fs_ncg);
679 wtfs(fsbtodb(&sblock, cgbase(&sblock, 0)) + sboff / sectorsize,
680 iobufsize - sboff, iobuf + sboff);
681
682 munmap(iobuf, iobufsize);
683 }
684
685 /*
686 * Initialize a cylinder (block) group.
687 */
688 void
689 initcg(uint cylno)
690 {
691 uint nblcg, i, j, sboff;
692 struct ext2fs_dinode *dp;
693
694 /*
695 * Make a copy of the superblock and group descriptors.
696 */
697 if (sblock.e2fs.e2fs_rev == E2FS_REV0 ||
698 (sblock.e2fs.e2fs_features_rocompat &
699 EXT2F_ROCOMPAT_SPARSESUPER) == 0 ||
700 cg_has_sb(cylno)) {
701 sblock.e2fs.e2fs_block_group_nr = cylno;
702 sboff = 0;
703 if (cgbase(&sblock, cylno) == 0) {
704 /* preserve data in bootblock in cg0 */
705 sboff = SBOFF;
706 }
707 e2fs_sbsave(&sblock.e2fs, (struct ext2fs *)(iobuf + sboff));
708 e2fs_cgsave(gd, (struct ext2_gd *)(iobuf +
709 sblock.e2fs_bsize * NBLOCK_SUPERBLOCK),
710 sizeof(struct ext2_gd) * sblock.e2fs_ncg);
711 /* write superblock and group descriptor backups */
712 wtfs(fsbtodb(&sblock, cgbase(&sblock, cylno)) +
713 sboff / sectorsize, iobufsize - sboff, iobuf + sboff);
714 }
715
716 /*
717 * Initialize block bitmap.
718 */
719 memset(buf, 0, sblock.e2fs_bsize);
720 if (cylno == (sblock.e2fs_ncg - 1)) {
721 /* The last group could have less blocks than e2fs_bpg. */
722 nblcg = sblock.e2fs.e2fs_bcount -
723 cgbase(&sblock, sblock.e2fs_ncg - 1);
724 for (i = nblcg; i < roundup(nblcg, NBBY); i++)
725 setbit(buf, i);
726 memset(&buf[i / NBBY], ~0U, sblock.e2fs.e2fs_bpg - i);
727 }
728 /* set overhead (superblock, group descriptor etc.) blocks used */
729 for (i = 0; i < cgoverhead(cylno) / NBBY; i++)
730 buf[i] = ~0;
731 i = i * NBBY;
732 for (; i < cgoverhead(cylno); i++)
733 setbit(buf, i);
734 wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_b_bitmap), sblock.e2fs_bsize,
735 buf);
736
737 /*
738 * Initialize inode bitmap.
739 *
740 * Assume e2fs_ipg is a multiple of NBBY since
741 * it's a multiple of e2fs_ipb (as we did above).
742 * Note even (possibly smaller) the last group has the same e2fs_ipg.
743 */
744 i = sblock.e2fs.e2fs_ipg / NBBY;
745 memset(buf, 0, i);
746 memset(buf + i, ~0U, sblock.e2fs_bsize - i);
747 if (cylno == 0) {
748 /* mark reserved inodes */
749 for (i = 1; i < EXT2_FIRSTINO; i++)
750 setbit(buf, EXT2_INO_INDEX(i));
751 }
752 wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_i_bitmap), sblock.e2fs_bsize,
753 buf);
754
755 /*
756 * Initialize inode tables.
757 *
758 * Just initialize generation numbers for NFS security.
759 * XXX: sys/ufs/ext2fs/ext2fs_alloc.c:ext2fs_valloc() seems
760 * to override these generated numbers.
761 */
762 memset(buf, 0, sblock.e2fs_bsize);
763 for (i = 0; i < sblock.e2fs_itpg; i++) {
764 for (j = 0; j < sblock.e2fs_ipb; j++) {
765 dp = (struct ext2fs_dinode *)(buf + inodesize * j);
766 /* h2fs32() just for consistency */
767 dp->e2di_gen = h2fs32(arc4random());
768 }
769 wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_i_tables + i),
770 sblock.e2fs_bsize, buf);
771 }
772 }
773
774 /*
775 * Zap possible lingering old superblock data
776 */
777 static void
778 zap_old_sblock(daddr_t sec)
779 {
780 static daddr_t cg0_data;
781 uint32_t oldfs[SBSIZE / sizeof(uint32_t)];
782 static const struct fsm {
783 uint32_t offset;
784 uint32_t magic;
785 uint32_t mask;
786 } fs_magics[] = {
787 {offsetof(struct ext2fs, e2fs_magic) / 4, E2FS_MAGIC, 0xffff},
788 {offsetof(struct ext2fs, e2fs_magic) / 4,
789 E2FS_MAGIC << 16, 0xffff0000},
790 {14, 0xef530000, 0xffff0000}, /* EXT2FS (big) */
791 {0x55c / 4, 0x00011954, ~0U}, /* FS_UFS1_MAGIC */
792 {0x55c / 4, 0x19540119, ~0U}, /* FS_UFS2_MAGIC */
793 {0, 0x70162, ~0U}, /* LFS_MAGIC */
794 {.offset = ~0U},
795 };
796 const struct fsm *fsm;
797
798 if (Nflag)
799 return;
800
801 /* don't override data before superblock */
802 if (sec < SBOFF / sectorsize)
803 return;
804
805 if (cg0_data == 0) {
806 cg0_data =
807 ((daddr_t)sblock.e2fs.e2fs_first_dblock + cgoverhead(0)) *
808 sblock.e2fs_bsize / sectorsize;
809 }
810
811 /* Ignore anything that is beyond our filesystem */
812 if (sec >= fssize)
813 return;
814 /* Zero anything inside our filesystem... */
815 if (sec >= sblock.e2fs.e2fs_first_dblock * bsize / sectorsize) {
816 /* ...unless we will write that area anyway */
817 if (sec >= cg0_data)
818 /* assume iobuf is zero'ed here */
819 wtfs(sec, roundup(SBSIZE, sectorsize), iobuf);
820 return;
821 }
822
823 /*
824 * The sector might contain boot code, so we must validate it
825 *
826 * XXX: ext2fs won't preserve data after SBOFF,
827 * but first_dblock could have a different value.
828 */
829 rdfs(sec, sizeof(oldfs), &oldfs);
830 for (fsm = fs_magics;; fsm++) {
831 uint32_t v;
832 if (fsm->mask == 0)
833 return;
834 v = oldfs[fsm->offset];
835 if ((v & fsm->mask) == fsm->magic ||
836 (bswap32(v) & fsm->mask) == fsm->magic)
837 break;
838 }
839
840 /* Just zap the magic number */
841 oldfs[fsm->offset] = 0;
842 wtfs(sec, sizeof(oldfs), &oldfs);
843 }
844
845 /*
846 * uint cgoverhead(uint c)
847 *
848 * Return a number of reserved blocks on the specified group.
849 * XXX: should be shared with src/sbin/fsck_ext2fs/setup.c
850 */
851 uint
852 cgoverhead(uint c)
853 {
854 uint overh;
855
856 overh = NBLOCK_BLOCK_BITMAP + NBLOCK_INODE_BITMAP + sblock.e2fs_itpg;
857
858 if (sblock.e2fs.e2fs_rev == E2FS_REV0 ||
859 (sblock.e2fs.e2fs_features_rocompat &
860 EXT2F_ROCOMPAT_SPARSESUPER) == 0 ||
861 cg_has_sb(c) != 0) {
862 overh += NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb;
863
864 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
865 (sblock.e2fs.e2fs_features_compat &
866 EXT2F_COMPAT_RESIZE) != 0)
867 overh += sblock.e2fs.e2fs_reserved_ngdb;
868 }
869
870 return overh;
871 }
872
873 /*
874 * Initialize the file system
875 */
876
877 #define LOSTDIR /* e2fsck complains if there is no lost+found */
878
879 #define PREDEFDIR 2
880
881 #ifdef LOSTDIR
882 #define PREDEFROOTDIR (PREDEFDIR + 1)
883 #else
884 #define PREDEFROOTDIR PREDEFDIR
885 #endif
886
887 struct ext2fs_direct root_dir[] = {
888 { EXT2_ROOTINO, 0, 1, 0, "." },
889 { EXT2_ROOTINO, 0, 2, 0, ".." },
890 #ifdef LOSTDIR
891 { EXT2_LOSTFOUNDINO, 0, 10, 0, "lost+found" },
892 #endif
893 };
894
895 #ifdef LOSTDIR
896 struct ext2fs_direct lost_found_dir[] = {
897 { EXT2_LOSTFOUNDINO, 0, 1, 0, "." },
898 { EXT2_ROOTINO, 0, 2, 0, ".." },
899 };
900 struct ext2fs_direct pad_dir = { 0, sizeof(struct ext2fs_direct), 0, 0, "" };
901 #endif
902
903 int
904 fsinit(const struct timeval *tv)
905 {
906 struct ext2fs_dinode node;
907 #ifdef LOSTDIR
908 uint i, nblks_lostfound, blk;
909 #endif
910
911 /*
912 * Initialize the inode for the resizefs feature
913 */
914 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
915 (sblock.e2fs.e2fs_features_compat & EXT2F_COMPAT_RESIZE) != 0)
916 init_resizeino(tv);
917
918 /*
919 * Initialize the node
920 */
921
922 #ifdef LOSTDIR
923 /*
924 * Create the lost+found directory
925 */
926 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
927 sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE) {
928 lost_found_dir[0].e2d_type = EXT2_FT_DIR;
929 lost_found_dir[1].e2d_type = EXT2_FT_DIR;
930 }
931 (void)makedir(lost_found_dir, __arraycount(lost_found_dir));
932
933 /* prepare a bit large directory for preserved files */
934 nblks_lostfound = EXT2_LOSTFOUNDSIZE / sblock.e2fs_bsize;
935 /* ...but only with direct blocks */
936 if (nblks_lostfound > NDADDR)
937 nblks_lostfound = NDADDR;
938
939 memset(&node, 0, sizeof(node));
940 node.e2di_mode = EXT2_IFDIR | EXT2_LOSTFOUNDUMASK;
941 node.e2di_uid = geteuid();
942 node.e2di_size = sblock.e2fs_bsize * nblks_lostfound;
943 node.e2di_atime = tv->tv_sec;
944 node.e2di_ctime = tv->tv_sec;
945 node.e2di_mtime = tv->tv_sec;
946 node.e2di_gid = getegid();
947 node.e2di_nlink = PREDEFDIR;
948 /* e2di_nblock is a number of disk blocks, not ext2fs blocks */
949 node.e2di_nblock = fsbtodb(&sblock, nblks_lostfound);
950 node.e2di_blocks[0] = alloc(sblock.e2fs_bsize, node.e2di_mode);
951 if (node.e2di_blocks[0] == 0) {
952 printf("%s: can't allocate block for lost+found\n", __func__);
953 return 0;
954 }
955 for (i = 1; i < nblks_lostfound; i++) {
956 blk = alloc(sblock.e2fs_bsize, 0);
957 if (blk == 0) {
958 printf("%s: can't allocate blocks for lost+found\n",
959 __func__);
960 return 0;
961 }
962 node.e2di_blocks[i] = blk;
963 }
964 wtfs(fsbtodb(&sblock, node.e2di_blocks[0]), sblock.e2fs_bsize, buf);
965 pad_dir.e2d_reclen = sblock.e2fs_bsize;
966 for (i = 1; i < nblks_lostfound; i++) {
967 memset(buf, 0, sblock.e2fs_bsize);
968 copy_dir(&pad_dir, (struct ext2fs_direct *)buf);
969 wtfs(fsbtodb(&sblock, node.e2di_blocks[i]), sblock.e2fs_bsize,
970 buf);
971 }
972 iput(&node, EXT2_LOSTFOUNDINO);
973 #endif
974 /*
975 * create the root directory
976 */
977 memset(&node, 0, sizeof(node));
978 if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
979 sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE) {
980 root_dir[0].e2d_type = EXT2_FT_DIR;
981 root_dir[1].e2d_type = EXT2_FT_DIR;
982 #ifdef LOSTDIR
983 root_dir[2].e2d_type = EXT2_FT_DIR;
984 #endif
985 }
986 node.e2di_mode = EXT2_IFDIR | EXT2_UMASK;
987 node.e2di_uid = geteuid();
988 node.e2di_size = makedir(root_dir, __arraycount(root_dir));
989 node.e2di_atime = tv->tv_sec;
990 node.e2di_ctime = tv->tv_sec;
991 node.e2di_mtime = tv->tv_sec;
992 node.e2di_gid = getegid();
993 node.e2di_nlink = PREDEFROOTDIR;
994 /* e2di_nblock is a number of disk block, not ext2fs block */
995 node.e2di_nblock = fsbtodb(&sblock, 1);
996 node.e2di_blocks[0] = alloc(node.e2di_size, node.e2di_mode);
997 if (node.e2di_blocks[0] == 0) {
998 printf("%s: can't allocate block for root dir\n", __func__);
999 return 0;
1000 }
1001 wtfs(fsbtodb(&sblock, node.e2di_blocks[0]), sblock.e2fs_bsize, buf);
1002 iput(&node, EXT2_ROOTINO);
1003 return 1;
1004 }
1005
1006 /*
1007 * Construct a set of directory entries in "buf".
1008 * return size of directory.
1009 */
1010 int
1011 makedir(struct ext2fs_direct *protodir, int entries)
1012 {
1013 uint8_t *cp;
1014 uint i, spcleft;
1015 uint dirblksiz;
1016
1017 dirblksiz = sblock.e2fs_bsize;
1018 memset(buf, 0, dirblksiz);
1019 spcleft = dirblksiz;
1020 for (cp = buf, i = 0; i < entries - 1; i++) {
1021 protodir[i].e2d_reclen = EXT2FS_DIRSIZ(protodir[i].e2d_namlen);
1022 copy_dir(&protodir[i], (struct ext2fs_direct *)cp);
1023 cp += protodir[i].e2d_reclen;
1024 spcleft -= protodir[i].e2d_reclen;
1025 }
1026 protodir[i].e2d_reclen = spcleft;
1027 copy_dir(&protodir[i], (struct ext2fs_direct *)cp);
1028 return dirblksiz;
1029 }
1030
1031 /*
1032 * Copy a direntry to a buffer, in fs byte order
1033 */
1034 static void
1035 copy_dir(struct ext2fs_direct *dir, struct ext2fs_direct *dbuf)
1036 {
1037
1038 memcpy(dbuf, dir, EXT2FS_DIRSIZ(dir->e2d_namlen));
1039 dbuf->e2d_ino = h2fs32(dir->e2d_ino);
1040 dbuf->e2d_reclen = h2fs16(dir->e2d_reclen);
1041 }
1042
1043 /*
1044 * void init_resizeino(const struct timeval *tv);
1045 *
1046 * Initialize the EXT2_RESEIZE_INO inode to preserve
1047 * reserved group descriptor blocks for future growth of this ext2fs.
1048 */
1049 void
1050 init_resizeino(const struct timeval *tv)
1051 {
1052 struct ext2fs_dinode node;
1053 uint64_t isize;
1054 uint32_t *dindir_block, *reserved_gdb;
1055 uint nblock, i, cylno, n;
1056
1057 memset(&node, 0, sizeof(node));
1058
1059 /*
1060 * Note this function only prepares required structures for
1061 * future resize. It's a quite different work to implement
1062 * a utility like resize_ext2fs(8) which handles actual
1063 * resize ops even on offline.
1064 *
1065 * Anyway, I'm not sure if there is any documentation about
1066 * this resize ext2fs feature and related data structures,
1067 * and I've written this function based on things what I see
1068 * on some existing implementation and real file system data
1069 * created by existing tools. To be honest, they are not
1070 * so easy to read, so I will try to implement it here without
1071 * any dumb optimization for people who would eventually
1072 * work on "yet another wheel" like resize_ext2fs(8).
1073 */
1074
1075 /*
1076 * I'm not sure what type is appropriate for this inode.
1077 * The release notes of e2fsprogs says they changed e2fsck to allow
1078 * IFREG for RESIZEINO since a certain resize tool used it. Hmm.
1079 */
1080 node.e2di_mode = EXT2_IFREG | EXT2_RESIZEINOUMASK;
1081 node.e2di_uid = geteuid();
1082 node.e2di_atime = tv->tv_sec;
1083 node.e2di_ctime = tv->tv_sec;
1084 node.e2di_mtime = tv->tv_sec;
1085 node.e2di_gid = getegid();
1086 node.e2di_nlink = 1;
1087
1088 /*
1089 * To preserve the reserved group descriptor blocks,
1090 * EXT2_RESIZEINO uses only double indirect reference
1091 * blocks in its inode entries.
1092 *
1093 * All entries for direct, single indirect and triple
1094 * indirect references are left zero'ed. Maybe it's safe
1095 * because no write operation will happen with this inode.
1096 *
1097 * We have to allocate a block for the first level double
1098 * indirect reference block. Indexes of inode entries in
1099 * this first level dindirect block are corresponding to
1100 * indexes of group descriptors including both used (e2fs_ngdb)
1101 * and reserved (e2fs_reserved_ngdb) group descriptor blocks.
1102 *
1103 * Inode entries of indexes for used (e2fs_ngdb) descriptors are
1104 * left zero'ed. Entries for reserved (e2fs_reserved_ngdb) ones
1105 * have block numbers of actual reserved group descriptors
1106 * allocated at block group zero. This means e2fs_reserved_ngdb
1107 * blocks are reserved as the second level dindirect reference
1108 * blocks, and they actually contain block numbers of indirect
1109 * references. It may be safe since they don't have to keep any
1110 * data yet.
1111 *
1112 * Each these second dindirect blocks (i.e. reserved group
1113 * descriptor blocks in the first block group) should have
1114 * block numbers of its backups in all other block groups.
1115 * I.e. reserved_ngdb[0] block in block group 0 contains block
1116 * numbers of resreved_ngdb[0] from group 1 through (e2fs_ncg - 1).
1117 * The number of backups can be determined by the
1118 * EXT2_ROCOMPAT_SPARSESUPER feature and cg_has_sb() macro
1119 * as done in the above initcg() function.
1120 */
1121
1122 /* set e2di_size which occupies whole blocks through DINDIR blocks */
1123 isize = (uint64_t)sblock.e2fs_bsize * NDADDR +
1124 (uint64_t)sblock.e2fs_bsize * NINDIR(&sblock) +
1125 (uint64_t)sblock.e2fs_bsize * NINDIR(&sblock) * NINDIR(&sblock);
1126 if (isize > UINT32_MAX &&
1127 (sblock.e2fs.e2fs_features_rocompat &
1128 EXT2F_ROCOMPAT_LARGEFILE) == 0) {
1129 /* XXX should enable it here and update all backups? */
1130 errx(EXIT_FAILURE, "%s: large_file rocompat feature is "
1131 "required to enable resize feature for this filesystem\n",
1132 __func__);
1133 }
1134 /* upper 32bit is stored into e2di_dacl on REV1 feature */
1135 node.e2di_size = isize & UINT32_MAX;
1136 node.e2di_dacl = isize >> 32;
1137
1138 #define SINGLE 0 /* index of single indirect block */
1139 #define DOUBLE 1 /* index of double indirect block */
1140 #define TRIPLE 2 /* index of triple indirect block */
1141
1142 /* zero out entries for direct references */
1143 for (i = 0; i < NDADDR; i++)
1144 node.e2di_blocks[i] = 0;
1145 /* also zero out entries for single and triple indirect references */
1146 node.e2di_blocks[NDADDR + SINGLE] = 0;
1147 node.e2di_blocks[NDADDR + TRIPLE] = 0;
1148
1149 /* allocate a block for the first level double indirect reference */
1150 node.e2di_blocks[NDADDR + DOUBLE] =
1151 alloc(sblock.e2fs_bsize, node.e2di_mode);
1152 if (node.e2di_blocks[NDADDR + DOUBLE] == 0)
1153 errx(EXIT_FAILURE, "%s: Can't allocate a dindirect block",
1154 __func__);
1155
1156 /* account this first block */
1157 nblock = fsbtodb(&sblock, 1);
1158
1159 /* allocate buffer to set data in the dindirect block */
1160 dindir_block = malloc(sblock.e2fs_bsize);
1161 if (dindir_block == NULL)
1162 errx(EXIT_FAILURE,
1163 "%s: Can't allocate buffer for a dindirect block",
1164 __func__);
1165
1166 /* allocate buffer to set data in the group descriptor blocks */
1167 reserved_gdb = malloc(sblock.e2fs_bsize);
1168 if (reserved_gdb == NULL)
1169 errx(EXIT_FAILURE,
1170 "%s: Can't allocate buffer for group descriptor blocks",
1171 __func__);
1172
1173 /*
1174 * Setup block entries in the first level dindirect blocks
1175 */
1176 for (i = 0; i < sblock.e2fs_ngdb; i++) {
1177 /* no need to handle used group descriptor blocks */
1178 dindir_block[i] = 0;
1179 }
1180 for (; i < sblock.e2fs_ngdb + sblock.e2fs.e2fs_reserved_ngdb; i++) {
1181 /*
1182 * point reserved group descriptor block in the first
1183 * (i.e. master) block group
1184 *
1185 * XXX: e2fsprogs seem to use "(i % NINDIR(&sblock))" here
1186 * to store maximum NINDIR(&sblock) reserved gdbs.
1187 * I'm not sure what will be done on future filesystem
1188 * shrink in that case on their way.
1189 */
1190 if (i >= NINDIR(&sblock))
1191 errx(EXIT_FAILURE, "%s: too many reserved "
1192 "group descriptors (%u) for resize inode",
1193 __func__, sblock.e2fs.e2fs_reserved_ngdb);
1194 dindir_block[i] =
1195 h2fs32(cgbase(&sblock, 0) + NBLOCK_SUPERBLOCK + i);
1196
1197 /*
1198 * Setup block entries in the second dindirect blocks
1199 * (which are primary reserved group descriptor blocks)
1200 * to point their backups.
1201 */
1202 for (n = 0, cylno = 1; cylno < sblock.e2fs_ncg; cylno++) {
1203 /* skip block groups without backup */
1204 if ((sblock.e2fs.e2fs_features_rocompat &
1205 EXT2F_ROCOMPAT_SPARSESUPER) != 0 &&
1206 cg_has_sb(cylno) == 0)
1207 continue;
1208
1209 if (n >= NINDIR(&sblock))
1210 errx(EXIT_FAILURE, "%s: too many block groups "
1211 "for the resize feature", __func__);
1212 /*
1213 * These blocks are already reserved in
1214 * initcg() so no need to use alloc() here.
1215 */
1216 reserved_gdb[n++] = h2fs32(cgbase(&sblock, cylno) +
1217 NBLOCK_SUPERBLOCK + i);
1218 nblock += fsbtodb(&sblock, 1);
1219 }
1220 for (; n < NINDIR(&sblock); n++)
1221 reserved_gdb[n] = 0;
1222
1223 /* write group descriptor block as the second dindirect refs */
1224 wtfs(fsbtodb(&sblock, fs2h32(dindir_block[i])),
1225 sblock.e2fs_bsize, reserved_gdb);
1226 nblock += fsbtodb(&sblock, 1);
1227 }
1228 for (; i < NINDIR(&sblock); i++) {
1229 /* leave trailing entries unallocated */
1230 dindir_block[i] = 0;
1231 }
1232 free(reserved_gdb);
1233
1234 /* finally write the first level dindirect block */
1235 wtfs(fsbtodb(&sblock, node.e2di_blocks[NDADDR + DOUBLE]),
1236 sblock.e2fs_bsize, dindir_block);
1237 free(dindir_block);
1238
1239 node.e2di_nblock = nblock;
1240 iput(&node, EXT2_RESIZEINO);
1241 }
1242
1243 /*
1244 * uint32_t alloc(uint32_t size, uint16_t mode)
1245 *
1246 * Allocate a block (from cylinder group 0)
1247 * Reference: src/sys/ufs/ext2fs/ext2fs_alloc.c:ext2fs_alloccg()
1248 */
1249 uint32_t
1250 alloc(uint32_t size, uint16_t mode)
1251 {
1252 uint32_t loc, bno;
1253 uint8_t *bbp;
1254 uint len, map, i;
1255
1256 if (gd[0].ext2bgd_nbfree == 0)
1257 return 0;
1258
1259 if (size > sblock.e2fs_bsize)
1260 return 0;
1261
1262 bbp = malloc(sblock.e2fs_bsize);
1263 if (bbp == NULL)
1264 return 0;
1265 rdfs(fsbtodb(&sblock, gd[0].ext2bgd_b_bitmap), sblock.e2fs_bsize, bbp);
1266
1267 /* XXX: kernel uses e2fs_fpg here */
1268 len = sblock.e2fs.e2fs_bpg / NBBY;
1269
1270 #if 0 /* no need block allocation for root or lost+found dir */
1271 for (loc = 0; loc < len; loc++) {
1272 if (bbp[loc] == 0) {
1273 bno = loc * NBBY;
1274 goto gotit;
1275 }
1276 }
1277 #endif
1278
1279 loc = skpc(~0U, len, bbp);
1280 if (loc == 0)
1281 return 0;
1282 loc = len - loc;
1283 map = bbp[loc];
1284 bno = loc * NBBY;
1285 for (i = 0; i < NBBY; i++, bno++) {
1286 if ((map & (1 << i)) == 0)
1287 goto gotit;
1288 }
1289 return 0;
1290
1291 gotit:
1292 if (isset(bbp, bno))
1293 errx(EXIT_FAILURE, "%s: inconsistent bitmap\n", __func__);
1294
1295 setbit(bbp, bno);
1296 wtfs(fsbtodb(&sblock, gd[0].ext2bgd_b_bitmap), sblock.e2fs_bsize, bbp);
1297 free(bbp);
1298 /* XXX: modified group descriptors won't be written into backups */
1299 gd[0].ext2bgd_nbfree--;
1300 if ((mode & EXT2_IFDIR) != 0)
1301 gd[0].ext2bgd_ndirs++;
1302 sblock.e2fs.e2fs_fbcount--;
1303
1304 return sblock.e2fs.e2fs_first_dblock + bno;
1305 }
1306
1307 /*
1308 * void iput(struct ext2fs_dinode *ip, ino_t ino)
1309 *
1310 * Put an inode entry into the corresponding table.
1311 */
1312 static void
1313 iput(struct ext2fs_dinode *ip, ino_t ino)
1314 {
1315 daddr_t d;
1316 uint c, i;
1317 struct ext2fs_dinode *dp;
1318 uint8_t *bp;
1319
1320 bp = malloc(sblock.e2fs_bsize);
1321 if (bp == NULL)
1322 errx(EXIT_FAILURE, "%s: can't allocate buffer for inode\n",
1323 __func__);
1324
1325 /*
1326 * Reserved inodes are allocated and accounted in initcg()
1327 * so skip checks of the bitmap and allocation for them.
1328 */
1329 if (ino >= EXT2_FIRSTINO) {
1330 c = ino_to_cg(&sblock, ino);
1331
1332 /* sanity check */
1333 if (gd[c].ext2bgd_nifree == 0)
1334 errx(EXIT_FAILURE,
1335 "%s: no free inode %" PRIu64 " in block group %u\n",
1336 __func__, (uint64_t)ino, c);
1337
1338 /* update inode bitmap */
1339 rdfs(fsbtodb(&sblock, gd[0].ext2bgd_i_bitmap),
1340 sblock.e2fs_bsize, bp);
1341
1342 /* more sanity */
1343 if (isset(bp, EXT2_INO_INDEX(ino)))
1344 errx(EXIT_FAILURE, "%s: inode %" PRIu64
1345 " already in use\n", __func__, (uint64_t)ino);
1346 setbit(bp, EXT2_INO_INDEX(ino));
1347 wtfs(fsbtodb(&sblock, gd[0].ext2bgd_i_bitmap),
1348 sblock.e2fs_bsize, bp);
1349 gd[c].ext2bgd_nifree--;
1350 sblock.e2fs.e2fs_ficount--;
1351 }
1352
1353 if (ino >= sblock.e2fs.e2fs_ipg * sblock.e2fs_ncg)
1354 errx(EXIT_FAILURE, "%s: inode value out of range (%" PRIu64
1355 ").\n", __func__, (uint64_t)ino);
1356
1357 /* update an inode entry in the table */
1358 d = fsbtodb(&sblock, ino_to_fsba(&sblock, ino));
1359 rdfs(d, sblock.e2fs_bsize, bp);
1360
1361 dp = (struct ext2fs_dinode *)(bp +
1362 inodesize * ino_to_fsbo(&sblock, ino));
1363 e2fs_isave(ip, dp);
1364 /* e2fs_i_bswap() doesn't swap e2di_blocks addrs */
1365 if ((ip->e2di_mode & EXT2_IFMT) != EXT2_IFLNK) {
1366 for (i = 0; i < NDADDR + NIADDR; i++)
1367 dp->e2di_blocks[i] = h2fs32(ip->e2di_blocks[i]);
1368 }
1369 /* h2fs32() just for consistency */
1370 dp->e2di_gen = h2fs32(arc4random());
1371
1372 wtfs(d, sblock.e2fs_bsize, bp);
1373 free(bp);
1374 }
1375
1376 /*
1377 * Read a block from the file system
1378 */
1379 void
1380 rdfs(daddr_t bno, int size, void *bf)
1381 {
1382 int n;
1383 off_t offset;
1384
1385 offset = bno;
1386 n = pread(fsi, bf, size, offset * sectorsize);
1387 if (n != size)
1388 err(EXIT_FAILURE, "%s: read error for sector %" PRId64,
1389 __func__, (int64_t)bno);
1390 }
1391
1392 /*
1393 * Write a block to the file system
1394 */
1395 void
1396 wtfs(daddr_t bno, int size, void *bf)
1397 {
1398 int n;
1399 off_t offset;
1400
1401 if (Nflag)
1402 return;
1403 offset = bno;
1404 n = pwrite(fso, bf, size, offset * sectorsize);
1405 if (n != size)
1406 err(EXIT_FAILURE, "%s: write error for sector %" PRId64,
1407 __func__, (int64_t)bno);
1408 }
1409
1410 int
1411 ilog2(uint val)
1412 {
1413
1414 if (val == 0 || !powerof2(val))
1415 errx(EXIT_FAILURE, "%s: %u is not a power of 2\n",
1416 __func__, val);
1417
1418 return ffs(val) - 1;
1419 }
1420
1421 /*
1422 * int skpc(int mask, size_t size, uint8_t *cp)
1423 *
1424 * Locate an unsigned character of value mask inside cp[].
1425 * (from src/sys/lib/libkern/skpc.c)
1426 */
1427 int
1428 skpc(int mask, size_t size, uint8_t *cp)
1429 {
1430 uint8_t *end;
1431
1432 end = &cp[size];
1433 while (cp < end && *cp == (uint8_t)mask)
1434 cp++;
1435
1436 return end - cp;
1437 }
1438