ext2_htree.c revision 296992
1/*-
2 * Copyright (c) 2010, 2012 Zheng Liu <lz@freebsd.org>
3 * Copyright (c) 2012, Vyacheslav Matyushin
4 * 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 REGENTS AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * $FreeBSD: stable/10/sys/fs/ext2fs/ext2_htree.c 296992 2016-03-17 19:28:15Z pfg $
28 */
29
30#include <sys/param.h>
31#include <sys/endian.h>
32#include <sys/systm.h>
33#include <sys/namei.h>
34#include <sys/bio.h>
35#include <sys/buf.h>
36#include <sys/endian.h>
37#include <sys/mount.h>
38#include <sys/vnode.h>
39#include <sys/malloc.h>
40#include <sys/dirent.h>
41#include <sys/sysctl.h>
42
43#include <ufs/ufs/dir.h>
44
45#include <fs/ext2fs/inode.h>
46#include <fs/ext2fs/ext2_mount.h>
47#include <fs/ext2fs/ext2fs.h>
48#include <fs/ext2fs/fs.h>
49#include <fs/ext2fs/ext2_extern.h>
50#include <fs/ext2fs/ext2_dinode.h>
51#include <fs/ext2fs/ext2_dir.h>
52#include <fs/ext2fs/htree.h>
53
54static void	ext2_append_entry(char *block, uint32_t blksize,
55		    struct ext2fs_direct_2 *last_entry,
56		    struct ext2fs_direct_2 *new_entry);
57static int	ext2_htree_append_block(struct vnode *vp, char *data,
58		    struct componentname *cnp, uint32_t blksize);
59static int	ext2_htree_check_next(struct inode *ip, uint32_t hash,
60		    const char *name, struct ext2fs_htree_lookup_info *info);
61static int	ext2_htree_cmp_sort_entry(const void *e1, const void *e2);
62static int	ext2_htree_find_leaf(struct inode *ip, const char *name,
63		    int namelen, uint32_t *hash, uint8_t *hash_version,
64		    struct ext2fs_htree_lookup_info *info);
65static uint32_t ext2_htree_get_block(struct ext2fs_htree_entry *ep);
66static uint16_t	ext2_htree_get_count(struct ext2fs_htree_entry *ep);
67static uint32_t ext2_htree_get_hash(struct ext2fs_htree_entry *ep);
68static uint16_t	ext2_htree_get_limit(struct ext2fs_htree_entry *ep);
69static void	ext2_htree_insert_entry_to_level(struct ext2fs_htree_lookup_level *level,
70		    uint32_t hash, uint32_t blk);
71static void	ext2_htree_insert_entry(struct ext2fs_htree_lookup_info *info,
72		    uint32_t hash, uint32_t blk);
73static uint32_t	ext2_htree_node_limit(struct inode *ip);
74static void	ext2_htree_set_block(struct ext2fs_htree_entry *ep,
75		    uint32_t blk);
76static void	ext2_htree_set_count(struct ext2fs_htree_entry *ep,
77		    uint16_t cnt);
78static void	ext2_htree_set_hash(struct ext2fs_htree_entry *ep,
79		    uint32_t hash);
80static void	ext2_htree_set_limit(struct ext2fs_htree_entry *ep,
81		    uint16_t limit);
82static int	ext2_htree_split_dirblock(char *block1, char *block2,
83		    uint32_t blksize, uint32_t *hash_seed, uint8_t hash_version,
84		    uint32_t *split_hash, struct  ext2fs_direct_2 *entry);
85static void	ext2_htree_release(struct ext2fs_htree_lookup_info *info);
86static uint32_t	ext2_htree_root_limit(struct inode *ip, int len);
87static int	ext2_htree_writebuf(struct ext2fs_htree_lookup_info *info);
88
89int
90ext2_htree_has_idx(struct inode *ip)
91{
92	if (EXT2_HAS_COMPAT_FEATURE(ip->i_e2fs, EXT2F_COMPAT_DIRHASHINDEX) &&
93	    ip->i_flag & IN_E3INDEX)
94		return (1);
95	else
96		return (0);
97}
98
99static int
100ext2_htree_check_next(struct inode *ip, uint32_t hash, const char *name,
101		struct ext2fs_htree_lookup_info *info)
102{
103	struct vnode *vp = ITOV(ip);
104	struct ext2fs_htree_lookup_level *level;
105	struct buf *bp;
106	uint32_t next_hash;
107	int idx = info->h_levels_num - 1;
108	int levels = 0;
109
110	do {
111		level = &info->h_levels[idx];
112		level->h_entry++;
113		if (level->h_entry < level->h_entries +
114		    ext2_htree_get_count(level->h_entries))
115			break;
116		if (idx == 0)
117			return (0);
118		idx--;
119		levels++;
120	} while (1);
121
122	next_hash = ext2_htree_get_hash(level->h_entry);
123	if ((hash & 1) == 0) {
124		if (hash != (next_hash & ~1))
125			return (0);
126	}
127
128	while (levels > 0) {
129		levels--;
130		if (ext2_blkatoff(vp, ext2_htree_get_block(level->h_entry) *
131		    ip->i_e2fs->e2fs_bsize, NULL, &bp) != 0)
132			return (0);
133		level = &info->h_levels[idx + 1];
134		brelse(level->h_bp);
135		level->h_bp = bp;
136		level->h_entry = level->h_entries =
137		    ((struct ext2fs_htree_node *)bp->b_data)->h_entries;
138	}
139
140	return (1);
141}
142
143static uint32_t
144ext2_htree_get_block(struct ext2fs_htree_entry *ep)
145{
146	return (ep->h_blk & 0x00FFFFFF);
147}
148
149static void
150ext2_htree_set_block(struct ext2fs_htree_entry *ep, uint32_t blk)
151{
152	ep->h_blk = blk;
153}
154
155static uint16_t
156ext2_htree_get_count(struct ext2fs_htree_entry *ep)
157{
158	return (((struct ext2fs_htree_count *)(ep))->h_entries_num);
159}
160
161static void
162ext2_htree_set_count(struct ext2fs_htree_entry *ep, uint16_t cnt)
163{
164	((struct ext2fs_htree_count *)(ep))->h_entries_num = cnt;
165}
166
167static uint32_t
168ext2_htree_get_hash(struct ext2fs_htree_entry *ep)
169{
170	return (ep->h_hash);
171}
172
173static uint16_t
174ext2_htree_get_limit(struct ext2fs_htree_entry *ep)
175{
176	return (((struct ext2fs_htree_count *)(ep))->h_entries_max);
177}
178
179static void
180ext2_htree_set_hash(struct ext2fs_htree_entry *ep, uint32_t hash)
181{
182	ep->h_hash = hash;
183}
184
185static void
186ext2_htree_set_limit(struct ext2fs_htree_entry *ep, uint16_t limit)
187{
188	((struct ext2fs_htree_count *)(ep))->h_entries_max = limit;
189}
190
191static void
192ext2_htree_release(struct ext2fs_htree_lookup_info *info)
193{
194	int i;
195
196	for (i = 0; i < info->h_levels_num; i++) {
197		struct buf *bp = info->h_levels[i].h_bp;
198		if (bp != NULL)
199			brelse(bp);
200	}
201}
202
203static uint32_t
204ext2_htree_root_limit(struct inode *ip, int len)
205{
206	uint32_t space;
207
208	space = ip->i_e2fs->e2fs_bsize - EXT2_DIR_REC_LEN(1) -
209	    EXT2_DIR_REC_LEN(2) - len;
210	return (space / sizeof(struct ext2fs_htree_entry));
211}
212
213static uint32_t
214ext2_htree_node_limit(struct inode *ip)
215{
216	struct m_ext2fs *fs;
217	uint32_t space;
218
219	fs = ip->i_e2fs;
220	space = fs->e2fs_bsize - EXT2_DIR_REC_LEN(0);
221
222	return (space / sizeof(struct ext2fs_htree_entry));
223}
224
225static int
226ext2_htree_find_leaf(struct inode *ip, const char *name, int namelen,
227		     uint32_t *hash, uint8_t *hash_ver,
228		     struct ext2fs_htree_lookup_info *info)
229{
230	struct vnode *vp;
231	struct ext2fs *fs;
232	struct m_ext2fs *m_fs;
233	struct buf *bp = NULL;
234	struct ext2fs_htree_root *rootp;
235	struct ext2fs_htree_entry *entp, *start, *end, *middle, *found;
236	struct ext2fs_htree_lookup_level *level_info;
237	uint32_t hash_major = 0, hash_minor = 0;
238	uint32_t levels, cnt;
239	uint8_t hash_version;
240
241	if (name == NULL || info == NULL)
242		return (-1);
243
244	vp = ITOV(ip);
245	fs = ip->i_e2fs->e2fs;
246	m_fs = ip->i_e2fs;
247
248	if (ext2_blkatoff(vp, 0, NULL, &bp) != 0)
249		return (-1);
250
251	info->h_levels_num = 1;
252	info->h_levels[0].h_bp = bp;
253	rootp = (struct ext2fs_htree_root *)bp->b_data;
254	if (rootp->h_info.h_hash_version != EXT2_HTREE_LEGACY &&
255	    rootp->h_info.h_hash_version != EXT2_HTREE_HALF_MD4 &&
256	    rootp->h_info.h_hash_version != EXT2_HTREE_TEA)
257		goto error;
258
259	hash_version = rootp->h_info.h_hash_version;
260	if (hash_version <= EXT2_HTREE_TEA)
261		hash_version += m_fs->e2fs_uhash;
262	*hash_ver = hash_version;
263
264	ext2_htree_hash(name, namelen, fs->e3fs_hash_seed,
265	    hash_version, &hash_major, &hash_minor);
266	*hash = hash_major;
267
268	if ((levels = rootp->h_info.h_ind_levels) > 1)
269		goto error;
270
271	entp = (struct ext2fs_htree_entry *)(((char *)&rootp->h_info) +
272	    rootp->h_info.h_info_len);
273
274	if (ext2_htree_get_limit(entp) !=
275	    ext2_htree_root_limit(ip, rootp->h_info.h_info_len))
276		goto error;
277
278	while (1) {
279		cnt = ext2_htree_get_count(entp);
280		if (cnt == 0 || cnt > ext2_htree_get_limit(entp))
281			goto error;
282
283		start = entp + 1;
284		end = entp + cnt - 1;
285		while (start <= end) {
286			middle = start + (end - start) / 2;
287			if (ext2_htree_get_hash(middle) > hash_major)
288				end = middle - 1;
289			else
290				start = middle + 1;
291		}
292		found = start - 1;
293
294		level_info = &(info->h_levels[info->h_levels_num - 1]);
295		level_info->h_bp = bp;
296		level_info->h_entries = entp;
297		level_info->h_entry = found;
298		if (levels == 0)
299			return (0);
300		levels--;
301		if (ext2_blkatoff(vp,
302		    ext2_htree_get_block(found) * m_fs->e2fs_bsize,
303		    NULL, &bp) != 0)
304			goto error;
305		entp = ((struct ext2fs_htree_node *)bp->b_data)->h_entries;
306		info->h_levels_num++;
307		info->h_levels[info->h_levels_num - 1].h_bp = bp;
308	}
309
310error:
311	ext2_htree_release(info);
312	return (-1);
313}
314
315/*
316 * Try to lookup a directory entry in HTree index
317 */
318int
319ext2_htree_lookup(struct inode *ip, const char *name, int namelen,
320		  struct buf **bpp, int *entryoffp, doff_t *offp,
321		  doff_t *prevoffp, doff_t *endusefulp,
322		  struct ext2fs_searchslot *ss)
323{
324	struct vnode *vp;
325	struct ext2fs_htree_lookup_info info;
326	struct ext2fs_htree_entry *leaf_node;
327	struct m_ext2fs *m_fs;
328	struct buf *bp;
329	uint32_t blk;
330	uint32_t dirhash;
331	uint32_t bsize;
332	uint8_t hash_version;
333	int search_next;
334	int found = 0;
335
336	m_fs = ip->i_e2fs;
337	bsize = m_fs->e2fs_bsize;
338	vp = ITOV(ip);
339
340	/* TODO: print error msg because we don't lookup '.' and '..' */
341
342	memset(&info, 0, sizeof(info));
343	if (ext2_htree_find_leaf(ip, name, namelen, &dirhash,
344	    &hash_version, &info))
345		return (-1);
346
347	do {
348		leaf_node = info.h_levels[info.h_levels_num - 1].h_entry;
349		blk = ext2_htree_get_block(leaf_node);
350		if (ext2_blkatoff(vp, blk * bsize, NULL, &bp) != 0) {
351			ext2_htree_release(&info);
352			return (-1);
353		}
354
355		*offp = blk * bsize;
356		*entryoffp = 0;
357		*prevoffp = blk * bsize;
358		*endusefulp = blk * bsize;
359
360		if (ss->slotstatus == NONE) {
361			ss->slotoffset = -1;
362			ss->slotfreespace = 0;
363		}
364
365		if (ext2_search_dirblock(ip, bp->b_data, &found,
366		    name, namelen, entryoffp, offp, prevoffp,
367		    endusefulp, ss) != 0) {
368			brelse(bp);
369			ext2_htree_release(&info);
370			return (-1);
371		}
372
373		if (found) {
374			*bpp = bp;
375			ext2_htree_release(&info);
376			return (0);
377		}
378
379		brelse(bp);
380		search_next = ext2_htree_check_next(ip, dirhash, name, &info);
381	} while (search_next);
382
383	ext2_htree_release(&info);
384	return (ENOENT);
385}
386
387static int
388ext2_htree_append_block(struct vnode *vp, char *data,
389			struct componentname *cnp, uint32_t blksize)
390{
391	struct iovec aiov;
392	struct uio auio;
393	struct inode *dp = VTOI(vp);
394	uint64_t cursize, newsize;
395	int error;
396
397	cursize = roundup(dp->i_size, blksize);
398	newsize = cursize + blksize;
399
400	auio.uio_offset = cursize;
401	auio.uio_resid = blksize;
402	aiov.iov_len = blksize;
403	aiov.iov_base = data;
404	auio.uio_iov = &aiov;
405	auio.uio_iovcnt = 1;
406	auio.uio_rw = UIO_WRITE;
407	auio.uio_segflg = UIO_SYSSPACE;
408	error = VOP_WRITE(vp, &auio, IO_SYNC, cnp->cn_cred);
409	if (!error)
410		dp->i_size = newsize;
411
412	return (error);
413}
414
415static int
416ext2_htree_writebuf(struct ext2fs_htree_lookup_info *info)
417{
418	int i, error;
419
420	for (i = 0; i < info->h_levels_num; i++) {
421		struct buf *bp = info->h_levels[i].h_bp;
422		error = bwrite(bp);
423		if (error)
424			return (error);
425	}
426
427	return (0);
428}
429
430static void
431ext2_htree_insert_entry_to_level(struct ext2fs_htree_lookup_level *level,
432				 uint32_t hash, uint32_t blk)
433{
434	struct ext2fs_htree_entry *target;
435	int entries_num;
436
437	target = level->h_entry + 1;
438	entries_num = ext2_htree_get_count(level->h_entries);
439
440	memmove(target + 1, target, (char *)(level->h_entries + entries_num) -
441	    (char *)target);
442	ext2_htree_set_block(target, blk);
443	ext2_htree_set_hash(target, hash);
444	ext2_htree_set_count(level->h_entries, entries_num + 1);
445}
446
447/*
448 * Insert an index entry to the index node.
449 */
450static void
451ext2_htree_insert_entry(struct ext2fs_htree_lookup_info *info,
452			uint32_t hash, uint32_t blk)
453{
454	struct ext2fs_htree_lookup_level *level;
455
456	level = &info->h_levels[info->h_levels_num - 1];
457	ext2_htree_insert_entry_to_level(level, hash, blk);
458}
459
460/*
461 * Compare two entry sort descriptors by name hash value.
462 * This is used together with qsort.
463 */
464static int
465ext2_htree_cmp_sort_entry(const void *e1, const void *e2)
466{
467	const struct ext2fs_htree_sort_entry *entry1, *entry2;
468
469	entry1 = (const struct ext2fs_htree_sort_entry *)e1;
470	entry2 = (const struct ext2fs_htree_sort_entry *)e2;
471
472	if (entry1->h_hash < entry2->h_hash)
473		return (-1);
474	if (entry1->h_hash > entry2->h_hash)
475		return (1);
476	return (0);
477}
478
479/*
480 * Append an entry to the end of the directory block.
481 */
482static void
483ext2_append_entry(char *block, uint32_t blksize,
484		  struct ext2fs_direct_2 *last_entry,
485		  struct ext2fs_direct_2 *new_entry)
486{
487	uint16_t entry_len;
488
489	entry_len = EXT2_DIR_REC_LEN(last_entry->e2d_namlen);
490	last_entry->e2d_reclen = entry_len;
491	last_entry = (struct ext2fs_direct_2 *)((char *)last_entry + entry_len);
492	new_entry->e2d_reclen = block + blksize - (char *)last_entry;
493	memcpy(last_entry, new_entry, EXT2_DIR_REC_LEN(new_entry->e2d_namlen));
494}
495
496/*
497 * Move half of entries from the old directory block to the new one.
498 */
499static int
500ext2_htree_split_dirblock(char *block1, char *block2, uint32_t blksize,
501			  uint32_t *hash_seed, uint8_t hash_version,
502			  uint32_t *split_hash, struct ext2fs_direct_2 *entry)
503{
504	int entry_cnt = 0;
505	int size = 0;
506	int i, k;
507	uint32_t offset;
508	uint16_t entry_len = 0;
509	uint32_t entry_hash;
510	struct ext2fs_direct_2 *ep, *last;
511	char *dest;
512	struct ext2fs_htree_sort_entry *sort_info;
513
514	ep = (struct ext2fs_direct_2 *)block1;
515	dest = block2;
516	sort_info = (struct ext2fs_htree_sort_entry *)
517	    ((char *)block2 + blksize);
518
519	/*
520	 * Calculate name hash value for the entry which is to be added.
521	 */
522	ext2_htree_hash(entry->e2d_name, entry->e2d_namlen, hash_seed,
523	    hash_version, &entry_hash, NULL);
524
525	/*
526	 * Fill in directory entry sort descriptors.
527	 */
528	while ((char *)ep < block1 + blksize) {
529		if (ep->e2d_ino && ep->e2d_namlen) {
530			entry_cnt++;
531			sort_info--;
532			sort_info->h_size = ep->e2d_reclen;
533			sort_info->h_offset = (char *)ep - block1;
534			ext2_htree_hash(ep->e2d_name, ep->e2d_namlen,
535			    hash_seed, hash_version,
536			    &sort_info->h_hash, NULL);
537		}
538		ep = (struct ext2fs_direct_2 *)
539		    ((char *)ep + ep->e2d_reclen);
540	}
541
542	/*
543	 * Sort directory entry descriptors by name hash value.
544	 */
545	qsort(sort_info, entry_cnt, sizeof(struct ext2fs_htree_sort_entry),
546	    ext2_htree_cmp_sort_entry);
547
548	/*
549	 * Count the number of entries to move to directory block 2.
550	 */
551	for (i = entry_cnt - 1; i >= 0; i--) {
552		if (sort_info[i].h_size + size > blksize / 2)
553			break;
554		size += sort_info[i].h_size;
555	}
556
557	*split_hash = sort_info[i + 1].h_hash;
558
559	/*
560	 * Set collision bit.
561	 */
562	if (*split_hash == sort_info[i].h_hash)
563		*split_hash += 1;
564
565	/*
566	 * Move half of directory entries from block 1 to block 2.
567	 */
568	for (k = i + 1; k < entry_cnt; k++) {
569		ep = (struct ext2fs_direct_2 *)((char *)block1 +
570		    sort_info[k].h_offset);
571		entry_len = EXT2_DIR_REC_LEN(ep->e2d_namlen);
572		memcpy(dest, ep, entry_len);
573		((struct ext2fs_direct_2 *)dest)->e2d_reclen = entry_len;
574		/* Mark directory entry as unused. */
575		ep->e2d_ino = 0;
576		dest += entry_len;
577	}
578	dest -= entry_len;
579
580	/* Shrink directory entries in block 1. */
581	last = (struct ext2fs_direct_2 *)block1;
582	entry_len = 0;
583	for (offset = 0; offset < blksize; ) {
584		ep = (struct ext2fs_direct_2 *)(block1 + offset);
585		offset += ep->e2d_reclen;
586		if (ep->e2d_ino) {
587			last = (struct ext2fs_direct_2 *)
588			   ((char *)last + entry_len);
589			entry_len = EXT2_DIR_REC_LEN(ep->e2d_namlen);
590			memcpy((void *)last, (void *)ep, entry_len);
591			last->e2d_reclen = entry_len;
592		}
593	}
594
595	if (entry_hash >= *split_hash) {
596		/* Add entry to block 2. */
597		ext2_append_entry(block2, blksize,
598		    (struct ext2fs_direct_2 *)dest, entry);
599
600		/* Adjust length field of last entry of block 1. */
601		last->e2d_reclen = block1 + blksize - (char *)last;
602	} else {
603		/* Add entry to block 1. */
604		ext2_append_entry(block1, blksize, last, entry);
605
606		/* Adjust length field of last entry of block 2. */
607		((struct ext2fs_direct_2 *)dest)->e2d_reclen =
608		    block2 + blksize - dest;
609	}
610
611	return (0);
612}
613
614/*
615 * Create an HTree index for a directory
616 */
617int
618ext2_htree_create_index(struct vnode *vp, struct componentname *cnp,
619			struct ext2fs_direct_2 *new_entry)
620{
621	struct buf *bp = NULL;
622	struct inode *dp;
623	struct ext2fs *fs;
624	struct m_ext2fs *m_fs;
625	struct ext2fs_direct_2 *ep, *dotdot;
626	struct ext2fs_htree_root *root;
627	struct ext2fs_htree_lookup_info info;
628	uint32_t blksize, dirlen, split_hash;
629	uint8_t hash_version;
630	char *buf1 = NULL;
631	char *buf2 = NULL;
632	int error = 0;
633
634	dp = VTOI(vp);
635	fs = dp->i_e2fs->e2fs;
636	m_fs = dp->i_e2fs;
637	blksize = m_fs->e2fs_bsize;
638
639	buf1 = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
640	buf2 = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
641
642	if ((error = ext2_blkatoff(vp, 0, NULL, &bp)) != 0)
643		goto out;
644
645	root = (struct ext2fs_htree_root *)bp->b_data;
646	dotdot = (struct ext2fs_direct_2 *)((char *)&(root->h_dotdot));
647	ep = (struct ext2fs_direct_2 *)((char *)dotdot + dotdot->e2d_reclen);
648	dirlen = (char *)root + blksize - (char *)ep;
649	memcpy(buf1, ep, dirlen);
650	ep = (struct ext2fs_direct_2 *)buf1;
651	while ((char *)ep < buf1 + dirlen)
652		ep = (struct ext2fs_direct_2 *)
653		    ((char *)ep + ep->e2d_reclen);
654	ep->e2d_reclen = buf1 + blksize - (char *)ep;
655
656	dp->i_flag |= IN_E3INDEX;
657
658	/*
659	 * Initialize index root.
660	 */
661	dotdot->e2d_reclen = blksize - EXT2_DIR_REC_LEN(1);
662	memset(&root->h_info, 0, sizeof(root->h_info));
663	root->h_info.h_hash_version = fs->e3fs_def_hash_version;
664	root->h_info.h_info_len = sizeof(root->h_info);
665	ext2_htree_set_block(root->h_entries, 1);
666	ext2_htree_set_count(root->h_entries, 1);
667	ext2_htree_set_limit(root->h_entries,
668	    ext2_htree_root_limit(dp, sizeof(root->h_info)));
669
670	memset(&info, 0, sizeof(info));
671	info.h_levels_num = 1;
672	info.h_levels[0].h_entries = root->h_entries;
673	info.h_levels[0].h_entry = root->h_entries;
674
675	hash_version = root->h_info.h_hash_version;
676	if (hash_version <= EXT2_HTREE_TEA)
677		hash_version += m_fs->e2fs_uhash;
678	ext2_htree_split_dirblock(buf1, buf2, blksize, fs->e3fs_hash_seed,
679	    hash_version, &split_hash, new_entry);
680	ext2_htree_insert_entry(&info, split_hash, 2);
681
682	/*
683	 * Write directory block 0.
684	 */
685	if (DOINGASYNC(vp)) {
686		bdwrite(bp);
687		error = 0;
688	} else {
689		error = bwrite(bp);
690	}
691	dp->i_flag |= IN_CHANGE | IN_UPDATE;
692	if (error)
693		goto out;
694
695	/*
696	 * Write directory block 1.
697	 */
698	error = ext2_htree_append_block(vp, buf1, cnp, blksize);
699	if (error)
700		goto out1;
701
702	/*
703	 * Write directory block 2.
704	 */
705	error = ext2_htree_append_block(vp, buf2, cnp, blksize);
706
707	free(buf1, M_TEMP);
708	free(buf2, M_TEMP);
709	return (error);
710out:
711	if (bp != NULL)
712		brelse(bp);
713out1:
714	free(buf1, M_TEMP);
715	free(buf2, M_TEMP);
716	return (error);
717}
718
719/*
720 * Add an entry to the directory using htree index.
721 */
722int
723ext2_htree_add_entry(struct vnode *dvp, struct ext2fs_direct_2 *entry,
724		     struct componentname *cnp)
725{
726	struct ext2fs_htree_entry *entries, *leaf_node;
727	struct ext2fs_htree_lookup_info info;
728	struct buf *bp = NULL;
729	struct ext2fs *fs;
730	struct m_ext2fs *m_fs;
731	struct inode *ip;
732	uint16_t ent_num;
733	uint32_t dirhash, split_hash;
734	uint32_t blksize, blknum;
735	uint64_t cursize, dirsize;
736	uint8_t hash_version;
737	char *newdirblock = NULL;
738	char *newidxblock = NULL;
739	struct ext2fs_htree_node *dst_node;
740	struct ext2fs_htree_entry *dst_entries;
741	struct ext2fs_htree_entry *root_entires;
742	struct buf *dst_bp = NULL;
743	int error, write_bp = 0, write_dst_bp = 0, write_info = 0;
744
745	ip = VTOI(dvp);
746	m_fs = ip->i_e2fs;
747	fs = m_fs->e2fs;
748	blksize = m_fs->e2fs_bsize;
749
750	if (ip->i_count != 0)
751		return ext2_add_entry(dvp, entry);
752
753	/* Target directory block is full, split it */
754	memset(&info, 0, sizeof(info));
755	error = ext2_htree_find_leaf(ip, entry->e2d_name, entry->e2d_namlen,
756	    &dirhash, &hash_version, &info);
757	if (error)
758		return (error);
759
760	entries = info.h_levels[info.h_levels_num - 1].h_entries;
761	ent_num = ext2_htree_get_count(entries);
762	if (ent_num == ext2_htree_get_limit(entries)) {
763		/* Split the index node. */
764		root_entires = info.h_levels[0].h_entries;
765		newidxblock = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
766		dst_node = (struct ext2fs_htree_node *)newidxblock;
767		dst_entries = dst_node->h_entries;
768		memset(&dst_node->h_fake_dirent, 0,
769		    sizeof(dst_node->h_fake_dirent));
770		dst_node->h_fake_dirent.e2d_reclen = blksize;
771
772		cursize = roundup(ip->i_size, blksize);
773		dirsize = cursize + blksize;
774		blknum = dirsize / blksize - 1;
775
776		error = ext2_htree_append_block(dvp, newidxblock,
777		    cnp, blksize);
778		if (error)
779			goto finish;
780		error = ext2_blkatoff(dvp, cursize, NULL, &dst_bp);
781		if (error)
782			goto finish;
783		dst_node = (struct ext2fs_htree_node *)dst_bp->b_data;
784		dst_entries = dst_node->h_entries;
785
786		if (info.h_levels_num == 2) {
787			uint16_t src_ent_num, dst_ent_num;
788
789			if (ext2_htree_get_count(root_entires) ==
790			    ext2_htree_get_limit(root_entires)) {
791				/* Directory index is full */
792				error = EIO;
793				goto finish;
794			}
795
796			src_ent_num = ent_num / 2;
797			dst_ent_num = ent_num - src_ent_num;
798			split_hash = ext2_htree_get_hash(entries + src_ent_num);
799
800			/* Move half of index entries to the new index node */
801			memcpy(dst_entries, entries + src_ent_num,
802			    dst_ent_num * sizeof(struct ext2fs_htree_entry));
803			ext2_htree_set_count(entries, src_ent_num);
804			ext2_htree_set_count(dst_entries, dst_ent_num);
805			ext2_htree_set_limit(dst_entries,
806			    ext2_htree_node_limit(ip));
807
808			if (info.h_levels[1].h_entry >= entries + src_ent_num) {
809				struct buf *tmp = info.h_levels[1].h_bp;
810				info.h_levels[1].h_bp = dst_bp;
811				dst_bp = tmp;
812
813				info.h_levels[1].h_entry =
814				    info.h_levels[1].h_entry -
815				    (entries + src_ent_num) +
816				    dst_entries;
817				info.h_levels[1].h_entries = dst_entries;
818			}
819			ext2_htree_insert_entry_to_level(&info.h_levels[0],
820			    split_hash, blknum);
821
822			/* Write new index node to disk */
823			error = bwrite(dst_bp);
824			ip->i_flag |= IN_CHANGE | IN_UPDATE;
825			if (error)
826				goto finish;
827			write_dst_bp = 1;
828		} else {
829			/* Create second level for htree index */
830			struct ext2fs_htree_root *idx_root;
831
832			memcpy(dst_entries, entries,
833			    ent_num * sizeof(struct ext2fs_htree_entry));
834			ext2_htree_set_limit(dst_entries,
835			    ext2_htree_node_limit(ip));
836
837			idx_root = (struct ext2fs_htree_root *)
838			    info.h_levels[0].h_bp->b_data;
839			idx_root->h_info.h_ind_levels = 1;
840
841			ext2_htree_set_count(entries, 1);
842			ext2_htree_set_block(entries, blknum);
843
844			info.h_levels_num = 2;
845			info.h_levels[1].h_entries = dst_entries;
846			info.h_levels[1].h_entry = info.h_levels[0].h_entry -
847			    info.h_levels[0].h_entries + dst_entries;
848			info.h_levels[1].h_bp = dst_bp;
849			dst_bp = NULL;
850		}
851	}
852
853	leaf_node = info.h_levels[info.h_levels_num - 1].h_entry;
854	blknum = ext2_htree_get_block(leaf_node);
855	error = ext2_blkatoff(dvp, blknum * blksize, NULL, &bp);
856	if (error)
857		goto finish;
858
859	/* Split target directory block */
860	newdirblock = malloc(blksize, M_TEMP, M_WAITOK | M_ZERO);
861	ext2_htree_split_dirblock((char *)bp->b_data, newdirblock, blksize,
862	    fs->e3fs_hash_seed, hash_version, &split_hash, entry);
863	cursize = roundup(ip->i_size, blksize);
864	dirsize = cursize + blksize;
865	blknum = dirsize / blksize - 1;
866
867	/* Add index entry for the new directory block */
868	ext2_htree_insert_entry(&info, split_hash, blknum);
869
870	/* Write the new directory block to the end of the directory */
871	error = ext2_htree_append_block(dvp, newdirblock, cnp, blksize);
872	if (error)
873		goto finish;
874
875	/* Write the target directory block */
876	error = bwrite(bp);
877	ip->i_flag |= IN_CHANGE | IN_UPDATE;
878	if (error)
879		goto finish;
880	write_bp = 1;
881
882	/* Write the index block */
883	error = ext2_htree_writebuf(&info);
884	if (!error)
885		write_info = 1;
886
887finish:
888	if (dst_bp != NULL && !write_dst_bp)
889		brelse(dst_bp);
890	if (bp != NULL && !write_bp)
891		brelse(bp);
892	if (newdirblock != NULL)
893		free(newdirblock, M_TEMP);
894	if (newidxblock != NULL)
895		free(newidxblock, M_TEMP);
896	if (!write_info)
897		ext2_htree_release(&info);
898	return (error);
899}
900