rehash.c revision 5797cb017cb8accbab8c69aaf83269c5d2d72e4e
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 "config.h"
49#include <string.h>
50#include <ctype.h>
51#include <errno.h>
52#include "e2fsck.h"
53#include "problem.h"
54
55struct fill_dir_struct {
56	char *buf;
57	struct ext2_inode *inode;
58	errcode_t err;
59	e2fsck_t ctx;
60	struct hash_entry *harray;
61	int max_array, num_array;
62	unsigned int dir_size;
63	int compress;
64	ino_t parent;
65};
66
67struct hash_entry {
68	ext2_dirhash_t	hash;
69	ext2_dirhash_t	minor_hash;
70	ino_t		ino;
71	struct ext2_dir_entry	*dir;
72};
73
74struct out_dir {
75	int		num;
76	int		max;
77	char		*buf;
78	ext2_dirhash_t	*hashes;
79};
80
81static int fill_dir_block(ext2_filsys fs,
82			  blk64_t *block_nr,
83			  e2_blkcnt_t blockcnt,
84			  blk64_t ref_block EXT2FS_ATTR((unused)),
85			  int ref_offset EXT2FS_ATTR((unused)),
86			  void *priv_data)
87{
88	struct fill_dir_struct	*fd = (struct fill_dir_struct *) priv_data;
89	struct hash_entry 	*new_array, *ent;
90	struct ext2_dir_entry 	*dirent;
91	char			*dir;
92	unsigned int		offset, dir_offset, rec_len;
93	int			hash_alg;
94
95	if (blockcnt < 0)
96		return 0;
97
98	offset = blockcnt * fs->blocksize;
99	if (offset + fs->blocksize > fd->inode->i_size) {
100		fd->err = EXT2_ET_DIR_CORRUPTED;
101		return BLOCK_ABORT;
102	}
103	dir = (fd->buf+offset);
104	if (HOLE_BLKADDR(*block_nr)) {
105		memset(dir, 0, fs->blocksize);
106		dirent = (struct ext2_dir_entry *) dir;
107		(void) ext2fs_set_rec_len(fs, fs->blocksize, dirent);
108	} else {
109		fd->err = ext2fs_read_dir_block3(fs, *block_nr, dir, 0);
110		if (fd->err)
111			return BLOCK_ABORT;
112	}
113	hash_alg = fs->super->s_def_hash_version;
114	if ((hash_alg <= EXT2_HASH_TEA) &&
115	    (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
116		hash_alg += 3;
117	/* While the directory block is "hot", index it. */
118	dir_offset = 0;
119	while (dir_offset < fs->blocksize) {
120		dirent = (struct ext2_dir_entry *) (dir + dir_offset);
121		(void) ext2fs_get_rec_len(fs, dirent, &rec_len);
122		if (((dir_offset + rec_len) > fs->blocksize) ||
123		    (rec_len < 8) ||
124		    ((rec_len % 4) != 0) ||
125		    (((dirent->name_len & 0xFF)+8U) > rec_len)) {
126			fd->err = EXT2_ET_DIR_CORRUPTED;
127			return BLOCK_ABORT;
128		}
129		dir_offset += rec_len;
130		if (dirent->inode == 0)
131			continue;
132		if (!fd->compress && ((dirent->name_len&0xFF) == 1) &&
133		    (dirent->name[0] == '.'))
134			continue;
135		if (!fd->compress && ((dirent->name_len&0xFF) == 2) &&
136		    (dirent->name[0] == '.') && (dirent->name[1] == '.')) {
137			fd->parent = dirent->inode;
138			continue;
139		}
140		if (fd->num_array >= fd->max_array) {
141			new_array = realloc(fd->harray,
142			    sizeof(struct hash_entry) * (fd->max_array+500));
143			if (!new_array) {
144				fd->err = ENOMEM;
145				return BLOCK_ABORT;
146			}
147			fd->harray = new_array;
148			fd->max_array += 500;
149		}
150		ent = fd->harray + fd->num_array++;
151		ent->dir = dirent;
152		fd->dir_size += EXT2_DIR_REC_LEN(dirent->name_len & 0xFF);
153		ent->ino = dirent->inode;
154		if (fd->compress)
155			ent->hash = ent->minor_hash = 0;
156		else {
157			fd->err = ext2fs_dirhash(hash_alg, dirent->name,
158						 dirent->name_len & 0xFF,
159						 fs->super->s_hash_seed,
160						 &ent->hash, &ent->minor_hash);
161			if (fd->err)
162				return BLOCK_ABORT;
163		}
164	}
165
166	return 0;
167}
168
169/* Used for sorting the hash entry */
170static EXT2_QSORT_TYPE ino_cmp(const void *a, const void *b)
171{
172	const struct hash_entry *he_a = (const struct hash_entry *) a;
173	const struct hash_entry *he_b = (const struct hash_entry *) b;
174
175	return (he_a->ino - he_b->ino);
176}
177
178/* Used for sorting the hash entry */
179static EXT2_QSORT_TYPE name_cmp(const void *a, const void *b)
180{
181	const struct hash_entry *he_a = (const struct hash_entry *) a;
182	const struct hash_entry *he_b = (const struct hash_entry *) b;
183	int	ret;
184	int	min_len;
185
186	min_len = he_a->dir->name_len;
187	if (min_len > he_b->dir->name_len)
188		min_len = he_b->dir->name_len;
189
190	ret = strncmp(he_a->dir->name, he_b->dir->name, min_len);
191	if (ret == 0) {
192		if (he_a->dir->name_len > he_b->dir->name_len)
193			ret = 1;
194		else if (he_a->dir->name_len < he_b->dir->name_len)
195			ret = -1;
196		else
197			ret = he_b->dir->inode - he_a->dir->inode;
198	}
199	return ret;
200}
201
202/* Used for sorting the hash entry */
203static EXT2_QSORT_TYPE hash_cmp(const void *a, const void *b)
204{
205	const struct hash_entry *he_a = (const struct hash_entry *) a;
206	const struct hash_entry *he_b = (const struct hash_entry *) b;
207	int	ret;
208
209	if (he_a->hash > he_b->hash)
210		ret = 1;
211	else if (he_a->hash < he_b->hash)
212		ret = -1;
213	else {
214		if (he_a->minor_hash > he_b->minor_hash)
215			ret = 1;
216		else if (he_a->minor_hash < he_b->minor_hash)
217			ret = -1;
218		else
219			ret = name_cmp(a, b);
220	}
221	return ret;
222}
223
224static errcode_t alloc_size_dir(ext2_filsys fs, struct out_dir *outdir,
225				int blocks)
226{
227	void			*new_mem;
228
229	if (outdir->max) {
230		new_mem = realloc(outdir->buf, blocks * fs->blocksize);
231		if (!new_mem)
232			return ENOMEM;
233		outdir->buf = new_mem;
234		new_mem = realloc(outdir->hashes,
235				  blocks * sizeof(ext2_dirhash_t));
236		if (!new_mem)
237			return ENOMEM;
238		outdir->hashes = new_mem;
239	} else {
240		outdir->buf = malloc(blocks * fs->blocksize);
241		outdir->hashes = malloc(blocks * sizeof(ext2_dirhash_t));
242		outdir->num = 0;
243	}
244	outdir->max = blocks;
245	return 0;
246}
247
248static void free_out_dir(struct out_dir *outdir)
249{
250	free(outdir->buf);
251	free(outdir->hashes);
252	outdir->max = 0;
253	outdir->num =0;
254}
255
256static errcode_t get_next_block(ext2_filsys fs, struct out_dir *outdir,
257			 char ** ret)
258{
259	errcode_t	retval;
260
261	if (outdir->num >= outdir->max) {
262		retval = alloc_size_dir(fs, outdir, outdir->max + 50);
263		if (retval)
264			return retval;
265	}
266	*ret = outdir->buf + (outdir->num++ * fs->blocksize);
267	memset(*ret, 0, fs->blocksize);
268	return 0;
269}
270
271/*
272 * This function is used to make a unique filename.  We do this by
273 * appending ~0, and then incrementing the number.  However, we cannot
274 * expand the length of the filename beyond the padding available in
275 * the directory entry.
276 */
277static void mutate_name(char *str, __u16 *len)
278{
279	int	i;
280	__u16	l = *len & 0xFF, h = *len & 0xff00;
281
282	/*
283	 * First check to see if it looks the name has been mutated
284	 * already
285	 */
286	for (i = l-1; i > 0; i--) {
287		if (!isdigit(str[i]))
288			break;
289	}
290	if ((i == l-1) || (str[i] != '~')) {
291		if (((l-1) & 3) < 2)
292			l += 2;
293		else
294			l = (l+3) & ~3;
295		str[l-2] = '~';
296		str[l-1] = '0';
297		*len = l | h;
298		return;
299	}
300	for (i = l-1; i >= 0; i--) {
301		if (isdigit(str[i])) {
302			if (str[i] == '9')
303				str[i] = '0';
304			else {
305				str[i]++;
306				return;
307			}
308			continue;
309		}
310		if (i == 1) {
311			if (str[0] == 'z')
312				str[0] = 'A';
313			else if (str[0] == 'Z') {
314				str[0] = '~';
315				str[1] = '0';
316			} else
317				str[0]++;
318		} else if (i > 0) {
319			str[i] = '1';
320			str[i-1] = '~';
321		} else {
322			if (str[0] == '~')
323				str[0] = 'a';
324			else
325				str[0]++;
326		}
327		break;
328	}
329}
330
331static int duplicate_search_and_fix(e2fsck_t ctx, ext2_filsys fs,
332				    ext2_ino_t ino,
333				    struct fill_dir_struct *fd)
334{
335	struct problem_context	pctx;
336	struct hash_entry 	*ent, *prev;
337	int			i, j;
338	int			fixed = 0;
339	char			new_name[256];
340	__u16			new_len;
341	int			hash_alg;
342
343	clear_problem_context(&pctx);
344	pctx.ino = ino;
345
346	hash_alg = fs->super->s_def_hash_version;
347	if ((hash_alg <= EXT2_HASH_TEA) &&
348	    (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
349		hash_alg += 3;
350
351	for (i=1; i < fd->num_array; i++) {
352		ent = fd->harray + i;
353		prev = ent - 1;
354		if (!ent->dir->inode ||
355		    ((ent->dir->name_len & 0xFF) !=
356		     (prev->dir->name_len & 0xFF)) ||
357		    (strncmp(ent->dir->name, prev->dir->name,
358			     ent->dir->name_len & 0xFF)))
359			continue;
360		pctx.dirent = ent->dir;
361		if ((ent->dir->inode == prev->dir->inode) &&
362		    fix_problem(ctx, PR_2_DUPLICATE_DIRENT, &pctx)) {
363			e2fsck_adjust_inode_count(ctx, ent->dir->inode, -1);
364			ent->dir->inode = 0;
365			fixed++;
366			continue;
367		}
368		memcpy(new_name, ent->dir->name, ent->dir->name_len & 0xFF);
369		new_len = ent->dir->name_len;
370		mutate_name(new_name, &new_len);
371		for (j=0; j < fd->num_array; j++) {
372			if ((i==j) ||
373			    ((new_len & 0xFF) !=
374			     (fd->harray[j].dir->name_len & 0xFF)) ||
375			    (strncmp(new_name, fd->harray[j].dir->name,
376				     new_len & 0xFF)))
377				continue;
378			mutate_name(new_name, &new_len);
379
380			j = -1;
381		}
382		new_name[new_len & 0xFF] = 0;
383		pctx.str = new_name;
384		if (fix_problem(ctx, PR_2_NON_UNIQUE_FILE, &pctx)) {
385			memcpy(ent->dir->name, new_name, new_len & 0xFF);
386			ent->dir->name_len = new_len;
387			ext2fs_dirhash(hash_alg, ent->dir->name,
388				       ent->dir->name_len & 0xFF,
389				       fs->super->s_hash_seed,
390				       &ent->hash, &ent->minor_hash);
391			fixed++;
392		}
393	}
394	return fixed;
395}
396
397
398static errcode_t copy_dir_entries(e2fsck_t ctx,
399				  struct fill_dir_struct *fd,
400				  struct out_dir *outdir)
401{
402	ext2_filsys 		fs = ctx->fs;
403	errcode_t		retval;
404	char			*block_start;
405	struct hash_entry 	*ent;
406	struct ext2_dir_entry	*dirent;
407	unsigned int		rec_len, prev_rec_len, left, slack, offset;
408	int			i;
409	ext2_dirhash_t		prev_hash;
410
411	if (ctx->htree_slack_percentage == 255) {
412		profile_get_uint(ctx->profile, "options",
413				 "indexed_dir_slack_percentage",
414				 0, 20,
415				 &ctx->htree_slack_percentage);
416		if (ctx->htree_slack_percentage > 100)
417			ctx->htree_slack_percentage = 20;
418	}
419
420	outdir->max = 0;
421	retval = alloc_size_dir(fs, outdir,
422				(fd->dir_size / fs->blocksize) + 2);
423	if (retval)
424		return retval;
425	outdir->num = fd->compress ? 0 : 1;
426	offset = 0;
427	outdir->hashes[0] = 0;
428	prev_hash = 1;
429	if ((retval = get_next_block(fs, outdir, &block_start)))
430		return retval;
431	dirent = (struct ext2_dir_entry *) block_start;
432	prev_rec_len = 0;
433	rec_len = 0;
434	left = fs->blocksize;
435	slack = fd->compress ? 12 :
436		(fs->blocksize * ctx->htree_slack_percentage)/100;
437	if (slack < 12)
438		slack = 12;
439	for (i = 0; i < fd->num_array; i++) {
440		ent = fd->harray + i;
441		if (ent->dir->inode == 0)
442			continue;
443		rec_len = EXT2_DIR_REC_LEN(ent->dir->name_len & 0xFF);
444		if (rec_len > left) {
445			if (left) {
446				left += prev_rec_len;
447				retval = ext2fs_set_rec_len(fs, left, dirent);
448				if (retval)
449					return retval;
450			}
451			if ((retval = get_next_block(fs, outdir,
452						      &block_start)))
453				return retval;
454			offset = 0;
455		}
456		left = fs->blocksize - offset;
457		dirent = (struct ext2_dir_entry *) (block_start + offset);
458		if (offset == 0) {
459			if (ent->hash == prev_hash)
460				outdir->hashes[outdir->num-1] = ent->hash | 1;
461			else
462				outdir->hashes[outdir->num-1] = ent->hash;
463		}
464		dirent->inode = ent->dir->inode;
465		dirent->name_len = ent->dir->name_len;
466		retval = ext2fs_set_rec_len(fs, rec_len, dirent);
467		if (retval)
468			return retval;
469		prev_rec_len = rec_len;
470		memcpy(dirent->name, ent->dir->name, dirent->name_len & 0xFF);
471		offset += rec_len;
472		left -= rec_len;
473		if (left < slack) {
474			prev_rec_len += left;
475			retval = ext2fs_set_rec_len(fs, prev_rec_len, dirent);
476			if (retval)
477				return retval;
478			offset += left;
479			left = 0;
480		}
481		prev_hash = ent->hash;
482	}
483	if (left)
484		retval = ext2fs_set_rec_len(fs, rec_len + left, dirent);
485
486	return retval;
487}
488
489
490static struct ext2_dx_root_info *set_root_node(ext2_filsys fs, char *buf,
491				    ext2_ino_t ino, ext2_ino_t parent)
492{
493	struct ext2_dir_entry 		*dir;
494	struct ext2_dx_root_info  	*root;
495	struct ext2_dx_countlimit	*limits;
496	int				filetype = 0;
497
498	if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_FILETYPE)
499		filetype = EXT2_FT_DIR << 8;
500
501	memset(buf, 0, fs->blocksize);
502	dir = (struct ext2_dir_entry *) buf;
503	dir->inode = ino;
504	dir->name[0] = '.';
505	dir->name_len = 1 | filetype;
506	dir->rec_len = 12;
507	dir = (struct ext2_dir_entry *) (buf + 12);
508	dir->inode = parent;
509	dir->name[0] = '.';
510	dir->name[1] = '.';
511	dir->name_len = 2 | filetype;
512	dir->rec_len = fs->blocksize - 12;
513
514	root = (struct ext2_dx_root_info *) (buf+24);
515	root->reserved_zero = 0;
516	root->hash_version = fs->super->s_def_hash_version;
517	root->info_length = 8;
518	root->indirect_levels = 0;
519	root->unused_flags = 0;
520
521	limits = (struct ext2_dx_countlimit *) (buf+32);
522	limits->limit = (fs->blocksize - 32) / sizeof(struct ext2_dx_entry);
523	limits->count = 0;
524
525	return root;
526}
527
528
529static struct ext2_dx_entry *set_int_node(ext2_filsys fs, char *buf)
530{
531	struct ext2_dir_entry 		*dir;
532	struct ext2_dx_countlimit	*limits;
533
534	memset(buf, 0, fs->blocksize);
535	dir = (struct ext2_dir_entry *) buf;
536	dir->inode = 0;
537	(void) ext2fs_set_rec_len(fs, fs->blocksize, dir);
538
539	limits = (struct ext2_dx_countlimit *) (buf+8);
540	limits->limit = (fs->blocksize - 8) / sizeof(struct ext2_dx_entry);
541	limits->count = 0;
542
543	return (struct ext2_dx_entry *) limits;
544}
545
546/*
547 * This function takes the leaf nodes which have been written in
548 * outdir, and populates the root node and any necessary interior nodes.
549 */
550static errcode_t calculate_tree(ext2_filsys fs,
551				struct out_dir *outdir,
552				ext2_ino_t ino,
553				ext2_ino_t parent)
554{
555	struct ext2_dx_root_info  	*root_info;
556	struct ext2_dx_entry 		*root, *dx_ent = 0;
557	struct ext2_dx_countlimit	*root_limit, *limit;
558	errcode_t			retval;
559	char				* block_start;
560	int				i, c1, c2, nblks;
561	int				limit_offset, root_offset;
562
563	root_info = set_root_node(fs, outdir->buf, ino, parent);
564	root_offset = limit_offset = ((char *) root_info - outdir->buf) +
565		root_info->info_length;
566	root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
567	c1 = root_limit->limit;
568	nblks = outdir->num;
569
570	/* Write out the pointer blocks */
571	if (nblks-1 <= c1) {
572		/* Just write out the root block, and we're done */
573		root = (struct ext2_dx_entry *) (outdir->buf + root_offset);
574		for (i=1; i < nblks; i++) {
575			root->block = ext2fs_cpu_to_le32(i);
576			if (i != 1)
577				root->hash =
578					ext2fs_cpu_to_le32(outdir->hashes[i]);
579			root++;
580			c1--;
581		}
582	} else {
583		c2 = 0;
584		limit = 0;
585		root_info->indirect_levels = 1;
586		for (i=1; i < nblks; i++) {
587			if (c1 == 0)
588				return ENOSPC;
589			if (c2 == 0) {
590				if (limit)
591					limit->limit = limit->count =
592		ext2fs_cpu_to_le16(limit->limit);
593				root = (struct ext2_dx_entry *)
594					(outdir->buf + root_offset);
595				root->block = ext2fs_cpu_to_le32(outdir->num);
596				if (i != 1)
597					root->hash =
598			ext2fs_cpu_to_le32(outdir->hashes[i]);
599				if ((retval =  get_next_block(fs, outdir,
600							      &block_start)))
601					return retval;
602				dx_ent = set_int_node(fs, block_start);
603				limit = (struct ext2_dx_countlimit *) dx_ent;
604				c2 = limit->limit;
605				root_offset += sizeof(struct ext2_dx_entry);
606				c1--;
607			}
608			dx_ent->block = ext2fs_cpu_to_le32(i);
609			if (c2 != limit->limit)
610				dx_ent->hash =
611					ext2fs_cpu_to_le32(outdir->hashes[i]);
612			dx_ent++;
613			c2--;
614		}
615		limit->count = ext2fs_cpu_to_le16(limit->limit - c2);
616		limit->limit = ext2fs_cpu_to_le16(limit->limit);
617	}
618	root_limit = (struct ext2_dx_countlimit *) (outdir->buf + limit_offset);
619	root_limit->count = ext2fs_cpu_to_le16(root_limit->limit - c1);
620	root_limit->limit = ext2fs_cpu_to_le16(root_limit->limit);
621
622	return 0;
623}
624
625struct write_dir_struct {
626	struct out_dir *outdir;
627	errcode_t	err;
628	e2fsck_t	ctx;
629	blk64_t		cleared;
630};
631
632/*
633 * Helper function which writes out a directory block.
634 */
635static int write_dir_block(ext2_filsys fs,
636			   blk64_t *block_nr,
637			   e2_blkcnt_t blockcnt,
638			   blk64_t ref_block EXT2FS_ATTR((unused)),
639			   int ref_offset EXT2FS_ATTR((unused)),
640			   void *priv_data)
641{
642	struct write_dir_struct	*wd = (struct write_dir_struct *) priv_data;
643	blk64_t	blk;
644	char	*dir;
645
646	if (*block_nr == 0)
647		return 0;
648	if (blockcnt >= wd->outdir->num) {
649		e2fsck_read_bitmaps(wd->ctx);
650		blk = *block_nr;
651		/*
652		 * In theory, we only release blocks from the end of the
653		 * directory file, so it's fine to clobber a whole cluster at
654		 * once.
655		 */
656		if (blk % EXT2FS_CLUSTER_RATIO(fs) == 0) {
657			ext2fs_unmark_block_bitmap2(wd->ctx->block_found_map,
658						    blk);
659			ext2fs_block_alloc_stats2(fs, blk, -1);
660			wd->cleared++;
661		}
662		*block_nr = 0;
663		return BLOCK_CHANGED;
664	}
665	if (blockcnt < 0)
666		return 0;
667
668	dir = wd->outdir->buf + (blockcnt * fs->blocksize);
669	wd->err = ext2fs_write_dir_block3(fs, *block_nr, dir, 0);
670	if (wd->err)
671		return BLOCK_ABORT;
672	return 0;
673}
674
675static errcode_t write_directory(e2fsck_t ctx, ext2_filsys fs,
676				 struct out_dir *outdir,
677				 ext2_ino_t ino, int compress)
678{
679	struct write_dir_struct wd;
680	errcode_t	retval;
681	struct ext2_inode 	inode;
682
683	retval = e2fsck_expand_directory(ctx, ino, -1, outdir->num);
684	if (retval)
685		return retval;
686
687	wd.outdir = outdir;
688	wd.err = 0;
689	wd.ctx = ctx;
690	wd.cleared = 0;
691
692	retval = ext2fs_block_iterate3(fs, ino, 0, 0,
693				       write_dir_block, &wd);
694	if (retval)
695		return retval;
696	if (wd.err)
697		return wd.err;
698
699	e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
700	if (compress)
701		inode.i_flags &= ~EXT2_INDEX_FL;
702	else
703		inode.i_flags |= EXT2_INDEX_FL;
704	inode.i_size = outdir->num * fs->blocksize;
705	ext2fs_iblk_sub_blocks(fs, &inode, wd.cleared);
706	e2fsck_write_inode(ctx, ino, &inode, "rehash_dir");
707
708	return 0;
709}
710
711errcode_t e2fsck_rehash_dir(e2fsck_t ctx, ext2_ino_t ino)
712{
713	ext2_filsys 		fs = ctx->fs;
714	errcode_t		retval;
715	struct ext2_inode 	inode;
716	char			*dir_buf = 0;
717	struct fill_dir_struct	fd;
718	struct out_dir		outdir;
719
720	outdir.max = outdir.num = 0;
721	outdir.buf = 0;
722	outdir.hashes = 0;
723	e2fsck_read_inode(ctx, ino, &inode, "rehash_dir");
724
725	retval = ENOMEM;
726	fd.harray = 0;
727	dir_buf = malloc(inode.i_size);
728	if (!dir_buf)
729		goto errout;
730
731	fd.max_array = inode.i_size / 32;
732	fd.num_array = 0;
733	fd.harray = malloc(fd.max_array * sizeof(struct hash_entry));
734	if (!fd.harray)
735		goto errout;
736
737	fd.ctx = ctx;
738	fd.buf = dir_buf;
739	fd.inode = &inode;
740	fd.err = 0;
741	fd.dir_size = 0;
742	fd.compress = 0;
743	if (!(fs->super->s_feature_compat & EXT2_FEATURE_COMPAT_DIR_INDEX) ||
744	    (inode.i_size / fs->blocksize) < 2)
745		fd.compress = 1;
746	fd.parent = 0;
747
748retry_nohash:
749	/* Read in the entire directory into memory */
750	retval = ext2fs_block_iterate3(fs, ino, 0, 0,
751				       fill_dir_block, &fd);
752	if (fd.err) {
753		retval = fd.err;
754		goto errout;
755	}
756
757	/*
758	 * If the entries read are less than a block, then don't index
759	 * the directory
760	 */
761	if (!fd.compress && (fd.dir_size < (fs->blocksize - 24))) {
762		fd.compress = 1;
763		fd.dir_size = 0;
764		fd.num_array = 0;
765		goto retry_nohash;
766	}
767
768#if 0
769	printf("%d entries (%d bytes) found in inode %d\n",
770	       fd.num_array, fd.dir_size, ino);
771#endif
772
773	/* Sort the list */
774resort:
775	if (fd.compress)
776		qsort(fd.harray+2, fd.num_array-2, sizeof(struct hash_entry),
777		      hash_cmp);
778	else
779		qsort(fd.harray, fd.num_array, sizeof(struct hash_entry),
780		      hash_cmp);
781
782	/*
783	 * Look for duplicates
784	 */
785	if (duplicate_search_and_fix(ctx, fs, ino, &fd))
786		goto resort;
787
788	if (ctx->options & E2F_OPT_NO) {
789		retval = 0;
790		goto errout;
791	}
792
793	/* Sort non-hashed directories by inode number */
794	if (fd.compress)
795		qsort(fd.harray+2, fd.num_array-2,
796		      sizeof(struct hash_entry), ino_cmp);
797
798	/*
799	 * Copy the directory entries.  In a htree directory these
800	 * will become the leaf nodes.
801	 */
802	retval = copy_dir_entries(ctx, &fd, &outdir);
803	if (retval)
804		goto errout;
805
806	free(dir_buf); dir_buf = 0;
807
808	if (!fd.compress) {
809		/* Calculate the interior nodes */
810		retval = calculate_tree(fs, &outdir, ino, fd.parent);
811		if (retval)
812			goto errout;
813	}
814
815	retval = write_directory(ctx, fs, &outdir, ino, fd.compress);
816	if (retval)
817		goto errout;
818
819errout:
820	free(dir_buf);
821	free(fd.harray);
822
823	free_out_dir(&outdir);
824	return retval;
825}
826
827void e2fsck_rehash_directories(e2fsck_t ctx)
828{
829	struct problem_context	pctx;
830#ifdef RESOURCE_TRACK
831	struct resource_track	rtrack;
832#endif
833	struct dir_info		*dir;
834	ext2_u32_iterate 	iter;
835	struct dir_info_iter *	dirinfo_iter = 0;
836	ext2_ino_t		ino;
837	errcode_t		retval;
838	int			cur, max, all_dirs, first = 1;
839
840	init_resource_track(&rtrack, ctx->fs->io);
841	all_dirs = ctx->options & E2F_OPT_COMPRESS_DIRS;
842
843	if (!ctx->dirs_to_hash && !all_dirs)
844		return;
845
846	e2fsck_get_lost_and_found(ctx, 0);
847
848	clear_problem_context(&pctx);
849
850	cur = 0;
851	if (all_dirs) {
852		dirinfo_iter = e2fsck_dir_info_iter_begin(ctx);
853		max = e2fsck_get_num_dirinfo(ctx);
854	} else {
855		retval = ext2fs_u32_list_iterate_begin(ctx->dirs_to_hash,
856						       &iter);
857		if (retval) {
858			pctx.errcode = retval;
859			fix_problem(ctx, PR_3A_OPTIMIZE_ITER, &pctx);
860			return;
861		}
862		max = ext2fs_u32_list_count(ctx->dirs_to_hash);
863	}
864	while (1) {
865		if (all_dirs) {
866			if ((dir = e2fsck_dir_info_iter(ctx,
867							dirinfo_iter)) == 0)
868				break;
869			ino = dir->ino;
870		} else {
871			if (!ext2fs_u32_list_iterate(iter, &ino))
872				break;
873		}
874		if (ino == ctx->lost_and_found)
875			continue;
876		pctx.dir = ino;
877		if (first) {
878			fix_problem(ctx, PR_3A_PASS_HEADER, &pctx);
879			first = 0;
880		}
881#if 0
882		fix_problem(ctx, PR_3A_OPTIMIZE_DIR, &pctx);
883#endif
884		pctx.errcode = e2fsck_rehash_dir(ctx, ino);
885		if (pctx.errcode) {
886			end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
887			fix_problem(ctx, PR_3A_OPTIMIZE_DIR_ERR, &pctx);
888		}
889		if (ctx->progress && !ctx->progress_fd)
890			e2fsck_simple_progress(ctx, "Rebuilding directory",
891			       100.0 * (float) (++cur) / (float) max, ino);
892	}
893	end_problem_latch(ctx, PR_LATCH_OPTIMIZE_DIR);
894	if (all_dirs)
895		e2fsck_dir_info_iter_end(ctx, dirinfo_iter);
896	else
897		ext2fs_u32_list_iterate_end(iter);
898
899	if (ctx->dirs_to_hash)
900		ext2fs_u32_list_free(ctx->dirs_to_hash);
901	ctx->dirs_to_hash = 0;
902
903	print_resource_track(ctx, "Pass 3A", &rtrack, ctx->fs->io);
904}
905