rehash.c revision e0ed7404719a9ddd2ba427a80db5365c8bad18c0
1/*
2 * rehash.c --- rebuild hash tree directories
3 *
4 * Copyright (C) 2002 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 * This algorithm is designed for simplicity of implementation and to
12 * pack the directory as much as possible.  It however requires twice
13 * as much memory as the size of the directory.  The maximum size
14 * directory supported using a 4k blocksize is roughly a gigabyte, and
15 * so there may very well be problems with machines that don't have
16 * virtual memory, and obscenely large directories.
17 *
18 * An alternate algorithm which is much more disk intensive could be
19 * written, and probably will need to be written in the future.  The
20 * design goals of such an algorithm are: (a) use (roughly) constant
21 * amounts of memory, no matter how large the directory, (b) the
22 * directory must be safe at all times, even if e2fsck is interrupted
23 * in the middle, (c) we must use minimal amounts of extra disk
24 * blocks.  This pretty much requires an incremental approach, where
25 * we are reading from one part of the directory, and inserting into
26 * the front half.  So the algorithm will have to keep track of a
27 * moving block boundary between the new tree and the old tree, and
28 * files will need to be moved from the old directory and inserted
29 * into the new tree.  If the new directory requires space which isn't
30 * yet available, blocks from the beginning part of the old directory
31 * may need to be moved to the end of the directory to make room for
32 * the new tree:
33 *
34 *    --------------------------------------------------------
35 *    |  new tree   |        | old tree                      |
36 *    --------------------------------------------------------
37 *                  ^ ptr    ^ptr
38 *                tail new   head old
39 *
40 * This is going to be a pain in the tuckus to implement, and will
41 * require a lot more disk accesses.  So I'm going to skip it for now;
42 * it's only really going to be an issue for really, really big
43 * filesystems (when we reach the level of tens of millions of files
44 * in a single directory).  It will probably be easier to simply
45 * require that e2fsck use VM first.
46 */
47
48#include <string.h>
49#include <ctype.h>
50#include <errno.h>
51#include "e2fsck.h"
52#include "problem.h"
53
54struct fill_dir_struct {
55	char *buf;
56	struct ext2_inode *inode;
57	errcode_t err;
58	e2fsck_t ctx;
59	struct hash_entry *harray;
60	int max_array, num_array;
61	unsigned int dir_size;
62	int compress;
63	ino_t parent;
64};
65
66struct hash_entry {
67	ext2_dirhash_t	hash;
68	ext2_dirhash_t	minor_hash;
69	ino_t		ino;
70	struct ext2_dir_entry	*dir;
71};
72
73struct out_dir {
74	int		num;
75	int		max;
76	char		*buf;
77	ext2_dirhash_t	*hashes;
78};
79
80static int fill_dir_block(ext2_filsys fs,
81			  blk64_t *block_nr,
82			  e2_blkcnt_t blockcnt,
83			  blk64_t ref_block EXT2FS_ATTR((unused)),
84			  int ref_offset EXT2FS_ATTR((unused)),
85			  void *priv_data)
86{
87	struct fill_dir_struct	*fd = (struct fill_dir_struct *) priv_data;
88	struct hash_entry 	*new_array, *ent;
89	struct ext2_dir_entry 	*dirent;
90	char			*dir;
91	unsigned int		offset, dir_offset, rec_len;
92	int			hash_alg;
93
94	if (blockcnt < 0)
95		return 0;
96
97	offset = blockcnt * fs->blocksize;
98	if (offset + fs->blocksize > fd->inode->i_size) {
99		fd->err = EXT2_ET_DIR_CORRUPTED;
100		return BLOCK_ABORT;
101	}
102	dir = (fd->buf+offset);
103	if (HOLE_BLKADDR(*block_nr)) {
104		memset(dir, 0, fs->blocksize);
105		dirent = (struct ext2_dir_entry *) dir;
106		(void) ext2fs_set_rec_len(fs, fs->blocksize, dirent);
107	} else {
108		fd->err = ext2fs_read_dir_block3(fs, *block_nr, dir, 0);
109		if (fd->err)
110			return BLOCK_ABORT;
111	}
112	hash_alg = fs->super->s_def_hash_version;
113	if ((hash_alg <= EXT2_HASH_TEA) &&
114	    (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
115		hash_alg += 3;
116	/* While the directory block is "hot", index it. */
117	dir_offset = 0;
118	while (dir_offset < fs->blocksize) {
119		dirent = (struct ext2_dir_entry *) (dir + dir_offset);
120		(void) ext2fs_get_rec_len(fs, dirent, &rec_len);
121		if (((dir_offset + rec_len) > fs->blocksize) ||
122		    (rec_len < 8) ||
123		    ((rec_len % 4) != 0) ||
124		    (((dirent->name_len & 0xFF)+8U) > rec_len)) {
125			fd->err = EXT2_ET_DIR_CORRUPTED;
126			return BLOCK_ABORT;
127		}
128		dir_offset += rec_len;
129		if (dirent->inode == 0)
130			continue;
131		if (!fd->compress && ((dirent->name_len&0xFF) == 1) &&
132		    (dirent->name[0] == '.'))
133			continue;
134		if (!fd->compress && ((dirent->name_len&0xFF) == 2) &&
135		    (dirent->name[0] == '.') && (dirent->name[1] == '.')) {
136			fd->parent = dirent->inode;
137			continue;
138		}
139		if (fd->num_array >= fd->max_array) {
140			new_array = realloc(fd->harray,
141			    sizeof(struct hash_entry) * (fd->max_array+500));
142			if (!new_array) {
143				fd->err = ENOMEM;
144				return BLOCK_ABORT;
145			}
146			fd->harray = new_array;
147			fd->max_array += 500;
148		}
149		ent = fd->harray + fd->num_array++;
150		ent->dir = dirent;
151		fd->dir_size += EXT2_DIR_REC_LEN(dirent->name_len & 0xFF);
152		ent->ino = dirent->inode;
153		if (fd->compress)
154			ent->hash = ent->minor_hash = 0;
155		else {
156			fd->err = ext2fs_dirhash(hash_alg, dirent->name,
157						 dirent->name_len & 0xFF,
158						 fs->super->s_hash_seed,
159						 &ent->hash, &ent->minor_hash);
160			if (fd->err)
161				return BLOCK_ABORT;
162		}
163	}
164
165	return 0;
166}
167
168/* Used for sorting the hash entry */
169static EXT2_QSORT_TYPE ino_cmp(const void *a, const void *b)
170{
171	const struct hash_entry *he_a = (const struct hash_entry *) a;
172	const struct hash_entry *he_b = (const struct hash_entry *) b;
173
174	return (he_a->ino - he_b->ino);
175}
176
177/* Used for sorting the hash entry */
178static EXT2_QSORT_TYPE name_cmp(const void *a, const void *b)
179{
180	const struct hash_entry *he_a = (const struct hash_entry *) a;
181	const struct hash_entry *he_b = (const struct hash_entry *) b;
182	int	ret;
183	int	min_len;
184
185	min_len = he_a->dir->name_len;
186	if (min_len > he_b->dir->name_len)
187		min_len = he_b->dir->name_len;
188
189	ret = strncmp(he_a->dir->name, he_b->dir->name, min_len);
190	if (ret == 0) {
191		if (he_a->dir->name_len > he_b->dir->name_len)
192			ret = 1;
193		else if (he_a->dir->name_len < he_b->dir->name_len)
194			ret = -1;
195		else
196			ret = he_b->dir->inode - he_a->dir->inode;
197	}
198	return ret;
199}
200
201/* Used for sorting the hash entry */
202static EXT2_QSORT_TYPE hash_cmp(const void *a, const void *b)
203{
204	const struct hash_entry *he_a = (const struct hash_entry *) a;
205	const struct hash_entry *he_b = (const struct hash_entry *) b;
206	int	ret;
207
208	if (he_a->hash > he_b->hash)
209		ret = 1;
210	else if (he_a->hash < he_b->hash)
211		ret = -1;
212	else {
213		if (he_a->minor_hash > he_b->minor_hash)
214			ret = 1;
215		else if (he_a->minor_hash < he_b->minor_hash)
216			ret = -1;
217		else
218			ret = name_cmp(a, b);
219	}
220	return ret;
221}
222
223static errcode_t alloc_size_dir(ext2_filsys fs, struct out_dir *outdir,
224				int blocks)
225{
226	void			*new_mem;
227
228	if (outdir->max) {
229		new_mem = realloc(outdir->buf, blocks * fs->blocksize);
230		if (!new_mem)
231			return ENOMEM;
232		outdir->buf = new_mem;
233		new_mem = realloc(outdir->hashes,
234				  blocks * sizeof(ext2_dirhash_t));
235		if (!new_mem)
236			return ENOMEM;
237		outdir->hashes = new_mem;
238	} else {
239		outdir->buf = malloc(blocks * fs->blocksize);
240		outdir->hashes = malloc(blocks * sizeof(ext2_dirhash_t));
241		outdir->num = 0;
242	}
243	outdir->max = blocks;
244	return 0;
245}
246
247static void free_out_dir(struct out_dir *outdir)
248{
249	free(outdir->buf);
250	free(outdir->hashes);
251	outdir->max = 0;
252	outdir->num =0;
253}
254
255static errcode_t get_next_block(ext2_filsys fs, struct out_dir *outdir,
256			 char ** ret)
257{
258	errcode_t	retval;
259
260	if (outdir->num >= outdir->max) {
261		retval = alloc_size_dir(fs, outdir, outdir->max + 50);
262		if (retval)
263			return retval;
264	}
265	*ret = outdir->buf + (outdir->num++ * fs->blocksize);
266	memset(*ret, 0, fs->blocksize);
267	return 0;
268}
269
270/*
271 * This function is used to make a unique filename.  We do this by
272 * appending ~0, and then incrementing the number.  However, we cannot
273 * expand the length of the filename beyond the padding available in
274 * the directory entry.
275 */
276static void mutate_name(char *str, __u16 *len)
277{
278	int	i;
279	__u16	l = *len & 0xFF, h = *len & 0xff00;
280
281	/*
282	 * First check to see if it looks the name has been mutated
283	 * already
284	 */
285	for (i = l-1; i > 0; i--) {
286		if (!isdigit(str[i]))
287			break;
288	}
289	if ((i == l-1) || (str[i] != '~')) {
290		if (((l-1) & 3) < 2)
291			l += 2;
292		else
293			l = (l+3) & ~3;
294		str[l-2] = '~';
295		str[l-1] = '0';
296		*len = l | h;
297		return;
298	}
299	for (i = l-1; i >= 0; i--) {
300		if (isdigit(str[i])) {
301			if (str[i] == '9')
302				str[i] = '0';
303			else {
304				str[i]++;
305				return;
306			}
307			continue;
308		}
309		if (i == 1) {
310			if (str[0] == 'z')
311				str[0] = 'A';
312			else if (str[0] == 'Z') {
313				str[0] = '~';
314				str[1] = '0';
315			} else
316				str[0]++;
317		} else if (i > 0) {
318			str[i] = '1';
319			str[i-1] = '~';
320		} else {
321			if (str[0] == '~')
322				str[0] = 'a';
323			else
324				str[0]++;
325		}
326		break;
327	}
328}
329
330static int duplicate_search_and_fix(e2fsck_t ctx, ext2_filsys fs,
331				    ext2_ino_t ino,
332				    struct fill_dir_struct *fd)
333{
334	struct problem_context	pctx;
335	struct hash_entry 	*ent, *prev;
336	int			i, j;
337	int			fixed = 0;
338	char			new_name[256];
339	__u16			new_len;
340	int			hash_alg;
341
342	clear_problem_context(&pctx);
343	pctx.ino = ino;
344
345	hash_alg = fs->super->s_def_hash_version;
346	if ((hash_alg <= EXT2_HASH_TEA) &&
347	    (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
348		hash_alg += 3;
349
350	for (i=1; i < fd->num_array; i++) {
351		ent = fd->harray + i;
352		prev = ent - 1;
353		if (!ent->dir->inode ||
354		    ((ent->dir->name_len & 0xFF) !=
355		     (prev->dir->name_len & 0xFF)) ||
356		    (strncmp(ent->dir->name, prev->dir->name,
357			     ent->dir->name_len & 0xFF)))
358			continue;
359		pctx.dirent = ent->dir;
360		if ((ent->dir->inode == prev->dir->inode) &&
361		    fix_problem(ctx, PR_2_DUPLICATE_DIRENT, &pctx)) {
362			e2fsck_adjust_inode_count(ctx, ent->dir->inode, -1);
363			ent->dir->inode = 0;
364			fixed++;
365			continue;
366		}
367		memcpy(new_name, ent->dir->name, ent->dir->name_len & 0xFF);
368		new_len = ent->dir->name_len;
369		mutate_name(new_name, &new_len);
370		for (j=0; j < fd->num_array; j++) {
371			if ((i==j) ||
372			    ((new_len & 0xFF) !=
373			     (fd->harray[j].dir->name_len & 0xFF)) ||
374			    (strncmp(new_name, fd->harray[j].dir->name,
375				     new_len & 0xFF)))
376				continue;
377			mutate_name(new_name, &new_len);
378
379			j = -1;
380		}
381		new_name[new_len & 0xFF] = 0;
382		pctx.str = new_name;
383		if (fix_problem(ctx, PR_2_NON_UNIQUE_FILE, &pctx)) {
384			memcpy(ent->dir->name, new_name, new_len & 0xFF);
385			ent->dir->name_len = new_len;
386			ext2fs_dirhash(hash_alg, ent->dir->name,
387				       ent->dir->name_len & 0xFF,
388				       fs->super->s_hash_seed,
389				       &ent->hash, &ent->minor_hash);
390			fixed++;
391		}
392	}
393	return fixed;
394}
395
396
397static errcode_t copy_dir_entries(e2fsck_t ctx,
398				  struct fill_dir_struct *fd,
399				  struct out_dir *outdir)
400{
401	ext2_filsys 		fs = ctx->fs;
402	errcode_t		retval;
403	char			*block_start;
404	struct hash_entry 	*ent;
405	struct ext2_dir_entry	*dirent;
406	unsigned int		rec_len, prev_rec_len, left, slack, offset;
407	int			i;
408	ext2_dirhash_t		prev_hash;
409
410	if (ctx->htree_slack_percentage == 255) {
411		profile_get_uint(ctx->profile, "options",
412				 "indexed_dir_slack_percentage",
413				 0, 20,
414				 &ctx->htree_slack_percentage);
415		if (ctx->htree_slack_percentage > 100)
416			ctx->htree_slack_percentage = 20;
417	}
418
419	outdir->max = 0;
420	retval = alloc_size_dir(fs, outdir,
421				(fd->dir_size / fs->blocksize) + 2);
422	if (retval)
423		return retval;
424	outdir->num = fd->compress ? 0 : 1;
425	offset = 0;
426	outdir->hashes[0] = 0;
427	prev_hash = 1;
428	if ((retval = get_next_block(fs, outdir, &block_start)))
429		return retval;
430	dirent = (struct ext2_dir_entry *) block_start;
431	prev_rec_len = 0;
432	rec_len = 0;
433	left = fs->blocksize;
434	slack = fd->compress ? 12 :
435		(fs->blocksize * ctx->htree_slack_percentage)/100;
436	if (slack < 12)
437		slack = 12;
438	for (i = 0; i < fd->num_array; i++) {
439		ent = fd->harray + i;
440		if (ent->dir->inode == 0)
441			continue;
442		rec_len = EXT2_DIR_REC_LEN(ent->dir->name_len & 0xFF);
443		if (rec_len > left) {
444			if (left) {
445				left += prev_rec_len;
446				retval = ext2fs_set_rec_len(fs, left, dirent);
447				if (retval)
448					return retval;
449			}
450			if ((retval = get_next_block(fs, outdir,
451						      &block_start)))
452				return retval;
453			offset = 0;
454		}
455		left = fs->blocksize - offset;
456		dirent = (struct ext2_dir_entry *) (block_start + offset);
457		if (offset == 0) {
458			if (ent->hash == prev_hash)
459				outdir->hashes[outdir->num-1] = ent->hash | 1;
460			else
461				outdir->hashes[outdir->num-1] = ent->hash;
462		}
463		dirent->inode = ent->dir->inode;
464		dirent->name_len = ent->dir->name_len;
465		retval = ext2fs_set_rec_len(fs, rec_len, dirent);
466		if (retval)
467			return retval;
468		prev_rec_len = rec_len;
469		memcpy(dirent->name, ent->dir->name, dirent->name_len & 0xFF);
470		offset += rec_len;
471		left -= rec_len;
472		if (left < slack) {
473			prev_rec_len += left;
474			retval = ext2fs_set_rec_len(fs, prev_rec_len, dirent);
475			if (retval)
476				return retval;
477			offset += left;
478			left = 0;
479		}
480		prev_hash = ent->hash;
481	}
482	if (left)
483		retval = ext2fs_set_rec_len(fs, rec_len + left, dirent);
484
485	return retval;
486}
487
488
489static struct ext2_dx_root_info *set_root_node(ext2_filsys fs, char *buf,
490				    ext2_ino_t ino, ext2_ino_t parent)
491{
492	struct ext2_dir_entry 		*dir;
493	struct ext2_dx_root_info  	*root;
494	struct ext2_dx_countlimit	*limits;
495	int				filetype = 0;
496
497	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_FILETYPE)
498		filetype = EXT2_FT_DIR << 8;
499
500	memset(buf, 0, fs->blocksize);
501	dir = (struct ext2_dir_entry *) buf;
502	dir->inode = ino;
503	dir->name[0] = '.';
504	dir->name_len = 1 | filetype;
505	dir->rec_len = 12;
506	dir = (struct ext2_dir_entry *) (buf + 12);
507	dir->inode = parent;
508	dir->name[0] = '.';
509	dir->name[1] = '.';
510	dir->name_len = 2 | filetype;
511	dir->rec_len = fs->blocksize - 12;
512
513	root = (struct ext2_dx_root_info *) (buf+24);
514	root->reserved_zero = 0;
515	root->hash_version = fs->super->s_def_hash_version;
516	root->info_length = 8;
517	root->indirect_levels = 0;
518	root->unused_flags = 0;
519
520	limits = (struct ext2_dx_countlimit *) (buf+32);
521	limits->limit = (fs->blocksize - 32) / sizeof(struct ext2_dx_entry);
522	limits->count = 0;
523
524	return root;
525}
526
527
528static struct ext2_dx_entry *set_int_node(ext2_filsys fs, char *buf)
529{
530	struct ext2_dir_entry 		*dir;
531	struct ext2_dx_countlimit	*limits;
532
533	memset(buf, 0, fs->blocksize);
534	dir = (struct ext2_dir_entry *) buf;
535	dir->inode = 0;
536	(void) ext2fs_set_rec_len(fs, fs->blocksize, dir);
537
538	limits = (struct ext2_dx_countlimit *) (buf+8);
539	limits->limit = (fs->blocksize - 8) / sizeof(struct ext2_dx_entry);
540	limits->count = 0;
541
542	return (struct ext2_dx_entry *) limits;
543}
544
545/*
546 * This function takes the leaf nodes which have been written in
547 * outdir, and populates the root node and any necessary interior nodes.
548 */
549static errcode_t calculate_tree(ext2_filsys fs,
550				struct out_dir *outdir,
551				ext2_ino_t ino,
552				ext2_ino_t parent)
553{
554	struct ext2_dx_root_info  	*root_info;
555	struct ext2_dx_entry 		*root, *dx_ent = 0;
556	struct ext2_dx_countlimit	*root_limit, *limit;
557	errcode_t			retval;
558	char				* block_start;
559	int				i, c1, c2, nblks;
560	int				limit_offset, root_offset;
561
562	root_info = set_root_node(fs, outdir->buf, ino, parent);
563	root_offset = limit_offset = ((char *) root_info - outdir->buf) +
564		root_info->info_length;
565	root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
566	c1 = root_limit->limit;
567	nblks = outdir->num;
568
569	/* Write out the pointer blocks */
570	if (nblks-1 <= c1) {
571		/* Just write out the root block, and we're done */
572		root = (struct ext2_dx_entry *) (outdir->buf + root_offset);
573		for (i=1; i < nblks; i++) {
574			root->block = ext2fs_cpu_to_le32(i);
575			if (i != 1)
576				root->hash =
577					ext2fs_cpu_to_le32(outdir->hashes[i]);
578			root++;
579			c1--;
580		}
581	} else {
582		c2 = 0;
583		limit = 0;
584		root_info->indirect_levels = 1;
585		for (i=1; i < nblks; i++) {
586			if (c1 == 0)
587				return ENOSPC;
588			if (c2 == 0) {
589				if (limit)
590					limit->limit = limit->count =
591		ext2fs_cpu_to_le16(limit->limit);
592				root = (struct ext2_dx_entry *)
593					(outdir->buf + root_offset);
594				root->block = ext2fs_cpu_to_le32(outdir->num);
595				if (i != 1)
596					root->hash =
597			ext2fs_cpu_to_le32(outdir->hashes[i]);
598				if ((retval =  get_next_block(fs, outdir,
599							      &block_start)))
600					return retval;
601				dx_ent = set_int_node(fs, block_start);
602				limit = (struct ext2_dx_countlimit *) dx_ent;
603				c2 = limit->limit;
604				root_offset += sizeof(struct ext2_dx_entry);
605				c1--;
606			}
607			dx_ent->block = ext2fs_cpu_to_le32(i);
608			if (c2 != limit->limit)
609				dx_ent->hash =
610					ext2fs_cpu_to_le32(outdir->hashes[i]);
611			dx_ent++;
612			c2--;
613		}
614		limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
615		limit->limit = ext2fs_cpu_to_le16(limit->limit);
616	}
617	root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
618	root_limit->count = ext2fs_cpu_to_le16(root_limit->limit - c1);
619	root_limit->limit = ext2fs_cpu_to_le16(root_limit->limit);
620
621	return 0;
622}
623
624struct write_dir_struct {
625	struct out_dir *outdir;
626	errcode_t	err;
627	e2fsck_t	ctx;
628	blk64_t		cleared;
629};
630
631/*
632 * Helper function which writes out a directory block.
633 */
634static int write_dir_block(ext2_filsys fs,
635			   blk64_t *block_nr,
636			   e2_blkcnt_t blockcnt,
637			   blk64_t ref_block EXT2FS_ATTR((unused)),
638			   int ref_offset EXT2FS_ATTR((unused)),
639			   void *priv_data)
640{
641	struct write_dir_struct	*wd = (struct write_dir_struct *) priv_data;
642	blk64_t	blk;
643	char	*dir;
644
645	if (*block_nr == 0)
646		return 0;
647	if (blockcnt >= wd->outdir->num) {
648		e2fsck_read_bitmaps(wd->ctx);
649		blk = *block_nr;
650		/*
651		 * In theory, we only release blocks from the end of the
652		 * directory file, so it's fine to clobber a whole cluster at
653		 * once.
654		 */
655		if (blk % EXT2FS_CLUSTER_RATIO(fs) == 0) {
656			ext2fs_unmark_block_bitmap2(wd->ctx->block_found_map,
657						    blk);
658			ext2fs_block_alloc_stats2(fs, blk, -1);
659			wd->cleared++;
660		}
661		*block_nr = 0;
662		return BLOCK_CHANGED;
663	}
664	if (blockcnt < 0)
665		return 0;
666
667	dir = wd->outdir->buf + (blockcnt * fs->blocksize);
668	wd->err = ext2fs_write_dir_block3(fs, *block_nr, dir, 0);
669	if (wd->err)
670		return BLOCK_ABORT;
671	return 0;
672}
673
674static errcode_t write_directory(e2fsck_t ctx, ext2_filsys fs,
675				 struct out_dir *outdir,
676				 ext2_ino_t ino, int compress)
677{
678	struct write_dir_struct wd;
679	errcode_t	retval;
680	struct ext2_inode 	inode;
681
682	retval = e2fsck_expand_directory(ctx, ino, -1, outdir->num);
683	if (retval)
684		return retval;
685
686	wd.outdir = outdir;
687	wd.err = 0;
688	wd.ctx = ctx;
689	wd.cleared = 0;
690
691	retval = ext2fs_block_iterate3(fs, ino, 0, 0,
692				       write_dir_block, &wd);
693	if (retval)
694		return retval;
695	if (wd.err)
696		return wd.err;
697
698	e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
699	if (compress)
700		inode.i_flags &= ~EXT2_INDEX_FL;
701	else
702		inode.i_flags |= EXT2_INDEX_FL;
703	inode.i_size = outdir->num * fs->blocksize;
704	ext2fs_iblk_sub_blocks(fs, &inode, wd.cleared);
705	e2fsck_write_inode(ctx, ino, &inode, "rehash_dir");
706
707	return 0;
708}
709
710errcode_t e2fsck_rehash_dir(e2fsck_t ctx, ext2_ino_t ino)
711{
712	ext2_filsys 		fs = ctx->fs;
713	errcode_t		retval;
714	struct ext2_inode 	inode;
715	char			*dir_buf = 0;
716	struct fill_dir_struct	fd;
717	struct out_dir		outdir;
718
719	outdir.max = outdir.num = 0;
720	outdir.buf = 0;
721	outdir.hashes = 0;
722	e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
723
724	retval = ENOMEM;
725	fd.harray = 0;
726	dir_buf = malloc(inode.i_size);
727	if (!dir_buf)
728		goto errout;
729
730	fd.max_array = inode.i_size / 32;
731	fd.num_array = 0;
732	fd.harray = malloc(fd.max_array * sizeof(struct hash_entry));
733	if (!fd.harray)
734		goto errout;
735
736	fd.ctx = ctx;
737	fd.buf = dir_buf;
738	fd.inode = &inode;
739	fd.err = 0;
740	fd.dir_size = 0;
741	fd.compress = 0;
742	if (!(fs->super->s_feature_compat & EXT2_FEATURE_COMPAT_DIR_INDEX) ||
743	    (inode.i_size / fs->blocksize) < 2)
744		fd.compress = 1;
745	fd.parent = 0;
746
747retry_nohash:
748	/* Read in the entire directory into memory */
749	retval = ext2fs_block_iterate3(fs, ino, 0, 0,
750				       fill_dir_block, &fd);
751	if (fd.err) {
752		retval = fd.err;
753		goto errout;
754	}
755
756	/*
757	 * If the entries read are less than a block, then don't index
758	 * the directory
759	 */
760	if (!fd.compress && (fd.dir_size < (fs->blocksize - 24))) {
761		fd.compress = 1;
762		fd.dir_size = 0;
763		fd.num_array = 0;
764		goto retry_nohash;
765	}
766
767#if 0
768	printf("%d entries (%d bytes) found in inode %d\n",
769	       fd.num_array, fd.dir_size, ino);
770#endif
771
772	/* Sort the list */
773resort:
774	if (fd.compress)
775		qsort(fd.harray+2, fd.num_array-2, sizeof(struct hash_entry),
776		      hash_cmp);
777	else
778		qsort(fd.harray, fd.num_array, sizeof(struct hash_entry),
779		      hash_cmp);
780
781	/*
782	 * Look for duplicates
783	 */
784	if (duplicate_search_and_fix(ctx, fs, ino, &fd))
785		goto resort;
786
787	if (ctx->options & E2F_OPT_NO) {
788		retval = 0;
789		goto errout;
790	}
791
792	/* Sort non-hashed directories by inode number */
793	if (fd.compress)
794		qsort(fd.harray+2, fd.num_array-2,
795		      sizeof(struct hash_entry), ino_cmp);
796
797	/*
798	 * Copy the directory entries.  In a htree directory these
799	 * will become the leaf nodes.
800	 */
801	retval = copy_dir_entries(ctx, &fd, &outdir);
802	if (retval)
803		goto errout;
804
805	free(dir_buf); dir_buf = 0;
806
807	if (!fd.compress) {
808		/* Calculate the interior nodes */
809		retval = calculate_tree(fs, &outdir, ino, fd.parent);
810		if (retval)
811			goto errout;
812	}
813
814	retval = write_directory(ctx, fs, &outdir, ino, fd.compress);
815	if (retval)
816		goto errout;
817
818errout:
819	free(dir_buf);
820	free(fd.harray);
821
822	free_out_dir(&outdir);
823	return retval;
824}
825
826void e2fsck_rehash_directories(e2fsck_t ctx)
827{
828	struct problem_context	pctx;
829#ifdef RESOURCE_TRACK
830	struct resource_track	rtrack;
831#endif
832	struct dir_info		*dir;
833	ext2_u32_iterate 	iter;
834	struct dir_info_iter *	dirinfo_iter = 0;
835	ext2_ino_t		ino;
836	errcode_t		retval;
837	int			cur, max, all_dirs, first = 1;
838
839	init_resource_track(&rtrack, ctx->fs->io);
840	all_dirs = ctx->options & E2F_OPT_COMPRESS_DIRS;
841
842	if (!ctx->dirs_to_hash && !all_dirs)
843		return;
844
845	e2fsck_get_lost_and_found(ctx, 0);
846
847	clear_problem_context(&pctx);
848
849	cur = 0;
850	if (all_dirs) {
851		dirinfo_iter = e2fsck_dir_info_iter_begin(ctx);
852		max = e2fsck_get_num_dirinfo(ctx);
853	} else {
854		retval = ext2fs_u32_list_iterate_begin(ctx->dirs_to_hash,
855						       &iter);
856		if (retval) {
857			pctx.errcode = retval;
858			fix_problem(ctx, PR_3A_OPTIMIZE_ITER, &pctx);
859			return;
860		}
861		max = ext2fs_u32_list_count(ctx->dirs_to_hash);
862	}
863	while (1) {
864		if (all_dirs) {
865			if ((dir = e2fsck_dir_info_iter(ctx,
866							dirinfo_iter)) == 0)
867				break;
868			ino = dir->ino;
869		} else {
870			if (!ext2fs_u32_list_iterate(iter, &ino))
871				break;
872		}
873		if (ino == ctx->lost_and_found)
874			continue;
875		pctx.dir = ino;
876		if (first) {
877			fix_problem(ctx, PR_3A_PASS_HEADER, &pctx);
878			first = 0;
879		}
880#if 0
881		fix_problem(ctx, PR_3A_OPTIMIZE_DIR, &pctx);
882#endif
883		pctx.errcode = e2fsck_rehash_dir(ctx, ino);
884		if (pctx.errcode) {
885			end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
886			fix_problem(ctx, PR_3A_OPTIMIZE_DIR_ERR, &pctx);
887		}
888		if (ctx->progress && !ctx->progress_fd)
889			e2fsck_simple_progress(ctx, "Rebuilding directory",
890			       100.0 * (float) (++cur) / (float) max, ino);
891	}
892	end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
893	if (all_dirs)
894		e2fsck_dir_info_iter_end(ctx, dirinfo_iter);
895	else
896		ext2fs_u32_list_iterate_end(iter);
897
898	if (ctx->dirs_to_hash)
899		ext2fs_u32_list_free(ctx->dirs_to_hash);
900	ctx->dirs_to_hash = 0;
901
902	print_resource_track(ctx, "Pass 3A", &rtrack, ctx->fs->io);
903}
904