xref: /openbmc/linux/fs/ocfs2/dir.c (revision a531b0c2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * dir.c
4  *
5  * Creates, reads, walks and deletes directory-nodes
6  *
7  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
8  *
9  *  Portions of this code from linux/fs/ext3/dir.c
10  *
11  *  Copyright (C) 1992, 1993, 1994, 1995
12  *  Remy Card (card@masi.ibp.fr)
13  *  Laboratoire MASI - Institut Blaise pascal
14  *  Universite Pierre et Marie Curie (Paris VI)
15  *
16  *   from
17  *
18  *   linux/fs/minix/dir.c
19  *
20  *   Copyright (C) 1991, 1992 Linus Torvalds
21  */
22 
23 #include <linux/fs.h>
24 #include <linux/types.h>
25 #include <linux/slab.h>
26 #include <linux/highmem.h>
27 #include <linux/quotaops.h>
28 #include <linux/sort.h>
29 #include <linux/iversion.h>
30 
31 #include <cluster/masklog.h>
32 
33 #include "ocfs2.h"
34 
35 #include "alloc.h"
36 #include "blockcheck.h"
37 #include "dir.h"
38 #include "dlmglue.h"
39 #include "extent_map.h"
40 #include "file.h"
41 #include "inode.h"
42 #include "journal.h"
43 #include "namei.h"
44 #include "suballoc.h"
45 #include "super.h"
46 #include "sysfile.h"
47 #include "uptodate.h"
48 #include "ocfs2_trace.h"
49 
50 #include "buffer_head_io.h"
51 
52 #define NAMEI_RA_CHUNKS  2
53 #define NAMEI_RA_BLOCKS  4
54 #define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
55 
56 static int ocfs2_do_extend_dir(struct super_block *sb,
57 			       handle_t *handle,
58 			       struct inode *dir,
59 			       struct buffer_head *parent_fe_bh,
60 			       struct ocfs2_alloc_context *data_ac,
61 			       struct ocfs2_alloc_context *meta_ac,
62 			       struct buffer_head **new_bh);
63 static int ocfs2_dir_indexed(struct inode *inode);
64 
65 /*
66  * These are distinct checks because future versions of the file system will
67  * want to have a trailing dirent structure independent of indexing.
68  */
69 static int ocfs2_supports_dir_trailer(struct inode *dir)
70 {
71 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
72 
73 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
74 		return 0;
75 
76 	return ocfs2_meta_ecc(osb) || ocfs2_dir_indexed(dir);
77 }
78 
79 /*
80  * "new' here refers to the point at which we're creating a new
81  * directory via "mkdir()", but also when we're expanding an inline
82  * directory. In either case, we don't yet have the indexing bit set
83  * on the directory, so the standard checks will fail in when metaecc
84  * is turned off. Only directory-initialization type functions should
85  * use this then. Everything else wants ocfs2_supports_dir_trailer()
86  */
87 static int ocfs2_new_dir_wants_trailer(struct inode *dir)
88 {
89 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
90 
91 	return ocfs2_meta_ecc(osb) ||
92 		ocfs2_supports_indexed_dirs(osb);
93 }
94 
95 static inline unsigned int ocfs2_dir_trailer_blk_off(struct super_block *sb)
96 {
97 	return sb->s_blocksize - sizeof(struct ocfs2_dir_block_trailer);
98 }
99 
100 #define ocfs2_trailer_from_bh(_bh, _sb) ((struct ocfs2_dir_block_trailer *) ((_bh)->b_data + ocfs2_dir_trailer_blk_off((_sb))))
101 
102 /* XXX ocfs2_block_dqtrailer() is similar but not quite - can we make
103  * them more consistent? */
104 struct ocfs2_dir_block_trailer *ocfs2_dir_trailer_from_size(int blocksize,
105 							    void *data)
106 {
107 	char *p = data;
108 
109 	p += blocksize - sizeof(struct ocfs2_dir_block_trailer);
110 	return (struct ocfs2_dir_block_trailer *)p;
111 }
112 
113 /*
114  * XXX: This is executed once on every dirent. We should consider optimizing
115  * it.
116  */
117 static int ocfs2_skip_dir_trailer(struct inode *dir,
118 				  struct ocfs2_dir_entry *de,
119 				  unsigned long offset,
120 				  unsigned long blklen)
121 {
122 	unsigned long toff = blklen - sizeof(struct ocfs2_dir_block_trailer);
123 
124 	if (!ocfs2_supports_dir_trailer(dir))
125 		return 0;
126 
127 	if (offset != toff)
128 		return 0;
129 
130 	return 1;
131 }
132 
133 static void ocfs2_init_dir_trailer(struct inode *inode,
134 				   struct buffer_head *bh, u16 rec_len)
135 {
136 	struct ocfs2_dir_block_trailer *trailer;
137 
138 	trailer = ocfs2_trailer_from_bh(bh, inode->i_sb);
139 	strcpy(trailer->db_signature, OCFS2_DIR_TRAILER_SIGNATURE);
140 	trailer->db_compat_rec_len =
141 			cpu_to_le16(sizeof(struct ocfs2_dir_block_trailer));
142 	trailer->db_parent_dinode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
143 	trailer->db_blkno = cpu_to_le64(bh->b_blocknr);
144 	trailer->db_free_rec_len = cpu_to_le16(rec_len);
145 }
146 /*
147  * Link an unindexed block with a dir trailer structure into the index free
148  * list. This function will modify dirdata_bh, but assumes you've already
149  * passed it to the journal.
150  */
151 static int ocfs2_dx_dir_link_trailer(struct inode *dir, handle_t *handle,
152 				     struct buffer_head *dx_root_bh,
153 				     struct buffer_head *dirdata_bh)
154 {
155 	int ret;
156 	struct ocfs2_dx_root_block *dx_root;
157 	struct ocfs2_dir_block_trailer *trailer;
158 
159 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
160 				      OCFS2_JOURNAL_ACCESS_WRITE);
161 	if (ret) {
162 		mlog_errno(ret);
163 		goto out;
164 	}
165 	trailer = ocfs2_trailer_from_bh(dirdata_bh, dir->i_sb);
166 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
167 
168 	trailer->db_free_next = dx_root->dr_free_blk;
169 	dx_root->dr_free_blk = cpu_to_le64(dirdata_bh->b_blocknr);
170 
171 	ocfs2_journal_dirty(handle, dx_root_bh);
172 
173 out:
174 	return ret;
175 }
176 
177 static int ocfs2_free_list_at_root(struct ocfs2_dir_lookup_result *res)
178 {
179 	return res->dl_prev_leaf_bh == NULL;
180 }
181 
182 void ocfs2_free_dir_lookup_result(struct ocfs2_dir_lookup_result *res)
183 {
184 	brelse(res->dl_dx_root_bh);
185 	brelse(res->dl_leaf_bh);
186 	brelse(res->dl_dx_leaf_bh);
187 	brelse(res->dl_prev_leaf_bh);
188 }
189 
190 static int ocfs2_dir_indexed(struct inode *inode)
191 {
192 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INDEXED_DIR_FL)
193 		return 1;
194 	return 0;
195 }
196 
197 static inline int ocfs2_dx_root_inline(struct ocfs2_dx_root_block *dx_root)
198 {
199 	return dx_root->dr_flags & OCFS2_DX_FLAG_INLINE;
200 }
201 
202 /*
203  * Hashing code adapted from ext3
204  */
205 #define DELTA 0x9E3779B9
206 
207 static void TEA_transform(__u32 buf[4], __u32 const in[])
208 {
209 	__u32	sum = 0;
210 	__u32	b0 = buf[0], b1 = buf[1];
211 	__u32	a = in[0], b = in[1], c = in[2], d = in[3];
212 	int	n = 16;
213 
214 	do {
215 		sum += DELTA;
216 		b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b);
217 		b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d);
218 	} while (--n);
219 
220 	buf[0] += b0;
221 	buf[1] += b1;
222 }
223 
224 static void str2hashbuf(const char *msg, int len, __u32 *buf, int num)
225 {
226 	__u32	pad, val;
227 	int	i;
228 
229 	pad = (__u32)len | ((__u32)len << 8);
230 	pad |= pad << 16;
231 
232 	val = pad;
233 	if (len > num*4)
234 		len = num * 4;
235 	for (i = 0; i < len; i++) {
236 		if ((i % 4) == 0)
237 			val = pad;
238 		val = msg[i] + (val << 8);
239 		if ((i % 4) == 3) {
240 			*buf++ = val;
241 			val = pad;
242 			num--;
243 		}
244 	}
245 	if (--num >= 0)
246 		*buf++ = val;
247 	while (--num >= 0)
248 		*buf++ = pad;
249 }
250 
251 static void ocfs2_dx_dir_name_hash(struct inode *dir, const char *name, int len,
252 				   struct ocfs2_dx_hinfo *hinfo)
253 {
254 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
255 	const char	*p;
256 	__u32		in[8], buf[4];
257 
258 	/*
259 	 * XXX: Is this really necessary, if the index is never looked
260 	 * at by readdir? Is a hash value of '0' a bad idea?
261 	 */
262 	if ((len == 1 && !strncmp(".", name, 1)) ||
263 	    (len == 2 && !strncmp("..", name, 2))) {
264 		buf[0] = buf[1] = 0;
265 		goto out;
266 	}
267 
268 #ifdef OCFS2_DEBUG_DX_DIRS
269 	/*
270 	 * This makes it very easy to debug indexing problems. We
271 	 * should never allow this to be selected without hand editing
272 	 * this file though.
273 	 */
274 	buf[0] = buf[1] = len;
275 	goto out;
276 #endif
277 
278 	memcpy(buf, osb->osb_dx_seed, sizeof(buf));
279 
280 	p = name;
281 	while (len > 0) {
282 		str2hashbuf(p, len, in, 4);
283 		TEA_transform(buf, in);
284 		len -= 16;
285 		p += 16;
286 	}
287 
288 out:
289 	hinfo->major_hash = buf[0];
290 	hinfo->minor_hash = buf[1];
291 }
292 
293 /*
294  * bh passed here can be an inode block or a dir data block, depending
295  * on the inode inline data flag.
296  */
297 static int ocfs2_check_dir_entry(struct inode * dir,
298 				 struct ocfs2_dir_entry * de,
299 				 struct buffer_head * bh,
300 				 unsigned long offset)
301 {
302 	const char *error_msg = NULL;
303 	const int rlen = le16_to_cpu(de->rec_len);
304 
305 	if (unlikely(rlen < OCFS2_DIR_REC_LEN(1)))
306 		error_msg = "rec_len is smaller than minimal";
307 	else if (unlikely(rlen % 4 != 0))
308 		error_msg = "rec_len % 4 != 0";
309 	else if (unlikely(rlen < OCFS2_DIR_REC_LEN(de->name_len)))
310 		error_msg = "rec_len is too small for name_len";
311 	else if (unlikely(
312 		 ((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize))
313 		error_msg = "directory entry across blocks";
314 
315 	if (unlikely(error_msg != NULL))
316 		mlog(ML_ERROR, "bad entry in directory #%llu: %s - "
317 		     "offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n",
318 		     (unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg,
319 		     offset, (unsigned long long)le64_to_cpu(de->inode), rlen,
320 		     de->name_len);
321 
322 	return error_msg == NULL ? 1 : 0;
323 }
324 
325 static inline int ocfs2_match(int len,
326 			      const char * const name,
327 			      struct ocfs2_dir_entry *de)
328 {
329 	if (len != de->name_len)
330 		return 0;
331 	if (!de->inode)
332 		return 0;
333 	return !memcmp(name, de->name, len);
334 }
335 
336 /*
337  * Returns 0 if not found, -1 on failure, and 1 on success
338  */
339 static inline int ocfs2_search_dirblock(struct buffer_head *bh,
340 					struct inode *dir,
341 					const char *name, int namelen,
342 					unsigned long offset,
343 					char *first_de,
344 					unsigned int bytes,
345 					struct ocfs2_dir_entry **res_dir)
346 {
347 	struct ocfs2_dir_entry *de;
348 	char *dlimit, *de_buf;
349 	int de_len;
350 	int ret = 0;
351 
352 	de_buf = first_de;
353 	dlimit = de_buf + bytes;
354 
355 	while (de_buf < dlimit) {
356 		/* this code is executed quadratically often */
357 		/* do minimal checking `by hand' */
358 
359 		de = (struct ocfs2_dir_entry *) de_buf;
360 
361 		if (de_buf + namelen <= dlimit &&
362 		    ocfs2_match(namelen, name, de)) {
363 			/* found a match - just to be sure, do a full check */
364 			if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
365 				ret = -1;
366 				goto bail;
367 			}
368 			*res_dir = de;
369 			ret = 1;
370 			goto bail;
371 		}
372 
373 		/* prevent looping on a bad block */
374 		de_len = le16_to_cpu(de->rec_len);
375 		if (de_len <= 0) {
376 			ret = -1;
377 			goto bail;
378 		}
379 
380 		de_buf += de_len;
381 		offset += de_len;
382 	}
383 
384 bail:
385 	trace_ocfs2_search_dirblock(ret);
386 	return ret;
387 }
388 
389 static struct buffer_head *ocfs2_find_entry_id(const char *name,
390 					       int namelen,
391 					       struct inode *dir,
392 					       struct ocfs2_dir_entry **res_dir)
393 {
394 	int ret, found;
395 	struct buffer_head *di_bh = NULL;
396 	struct ocfs2_dinode *di;
397 	struct ocfs2_inline_data *data;
398 
399 	ret = ocfs2_read_inode_block(dir, &di_bh);
400 	if (ret) {
401 		mlog_errno(ret);
402 		goto out;
403 	}
404 
405 	di = (struct ocfs2_dinode *)di_bh->b_data;
406 	data = &di->id2.i_data;
407 
408 	found = ocfs2_search_dirblock(di_bh, dir, name, namelen, 0,
409 				      data->id_data, i_size_read(dir), res_dir);
410 	if (found == 1)
411 		return di_bh;
412 
413 	brelse(di_bh);
414 out:
415 	return NULL;
416 }
417 
418 static int ocfs2_validate_dir_block(struct super_block *sb,
419 				    struct buffer_head *bh)
420 {
421 	int rc;
422 	struct ocfs2_dir_block_trailer *trailer =
423 		ocfs2_trailer_from_bh(bh, sb);
424 
425 
426 	/*
427 	 * We don't validate dirents here, that's handled
428 	 * in-place when the code walks them.
429 	 */
430 	trace_ocfs2_validate_dir_block((unsigned long long)bh->b_blocknr);
431 
432 	BUG_ON(!buffer_uptodate(bh));
433 
434 	/*
435 	 * If the ecc fails, we return the error but otherwise
436 	 * leave the filesystem running.  We know any error is
437 	 * local to this block.
438 	 *
439 	 * Note that we are safe to call this even if the directory
440 	 * doesn't have a trailer.  Filesystems without metaecc will do
441 	 * nothing, and filesystems with it will have one.
442 	 */
443 	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &trailer->db_check);
444 	if (rc)
445 		mlog(ML_ERROR, "Checksum failed for dinode %llu\n",
446 		     (unsigned long long)bh->b_blocknr);
447 
448 	return rc;
449 }
450 
451 /*
452  * Validate a directory trailer.
453  *
454  * We check the trailer here rather than in ocfs2_validate_dir_block()
455  * because that function doesn't have the inode to test.
456  */
457 static int ocfs2_check_dir_trailer(struct inode *dir, struct buffer_head *bh)
458 {
459 	int rc = 0;
460 	struct ocfs2_dir_block_trailer *trailer;
461 
462 	trailer = ocfs2_trailer_from_bh(bh, dir->i_sb);
463 	if (!OCFS2_IS_VALID_DIR_TRAILER(trailer)) {
464 		rc = ocfs2_error(dir->i_sb,
465 				 "Invalid dirblock #%llu: signature = %.*s\n",
466 				 (unsigned long long)bh->b_blocknr, 7,
467 				 trailer->db_signature);
468 		goto out;
469 	}
470 	if (le64_to_cpu(trailer->db_blkno) != bh->b_blocknr) {
471 		rc = ocfs2_error(dir->i_sb,
472 				 "Directory block #%llu has an invalid db_blkno of %llu\n",
473 				 (unsigned long long)bh->b_blocknr,
474 				 (unsigned long long)le64_to_cpu(trailer->db_blkno));
475 		goto out;
476 	}
477 	if (le64_to_cpu(trailer->db_parent_dinode) !=
478 	    OCFS2_I(dir)->ip_blkno) {
479 		rc = ocfs2_error(dir->i_sb,
480 				 "Directory block #%llu on dinode #%llu has an invalid parent_dinode of %llu\n",
481 				 (unsigned long long)bh->b_blocknr,
482 				 (unsigned long long)OCFS2_I(dir)->ip_blkno,
483 				 (unsigned long long)le64_to_cpu(trailer->db_blkno));
484 		goto out;
485 	}
486 out:
487 	return rc;
488 }
489 
490 /*
491  * This function forces all errors to -EIO for consistency with its
492  * predecessor, ocfs2_bread().  We haven't audited what returning the
493  * real error codes would do to callers.  We log the real codes with
494  * mlog_errno() before we squash them.
495  */
496 static int ocfs2_read_dir_block(struct inode *inode, u64 v_block,
497 				struct buffer_head **bh, int flags)
498 {
499 	int rc = 0;
500 	struct buffer_head *tmp = *bh;
501 
502 	rc = ocfs2_read_virt_blocks(inode, v_block, 1, &tmp, flags,
503 				    ocfs2_validate_dir_block);
504 	if (rc) {
505 		mlog_errno(rc);
506 		goto out;
507 	}
508 
509 	if (!(flags & OCFS2_BH_READAHEAD) &&
510 	    ocfs2_supports_dir_trailer(inode)) {
511 		rc = ocfs2_check_dir_trailer(inode, tmp);
512 		if (rc) {
513 			if (!*bh)
514 				brelse(tmp);
515 			mlog_errno(rc);
516 			goto out;
517 		}
518 	}
519 
520 	/* If ocfs2_read_virt_blocks() got us a new bh, pass it up. */
521 	if (!*bh)
522 		*bh = tmp;
523 
524 out:
525 	return rc ? -EIO : 0;
526 }
527 
528 /*
529  * Read the block at 'phys' which belongs to this directory
530  * inode. This function does no virtual->physical block translation -
531  * what's passed in is assumed to be a valid directory block.
532  */
533 static int ocfs2_read_dir_block_direct(struct inode *dir, u64 phys,
534 				       struct buffer_head **bh)
535 {
536 	int ret;
537 	struct buffer_head *tmp = *bh;
538 
539 	ret = ocfs2_read_block(INODE_CACHE(dir), phys, &tmp,
540 			       ocfs2_validate_dir_block);
541 	if (ret) {
542 		mlog_errno(ret);
543 		goto out;
544 	}
545 
546 	if (ocfs2_supports_dir_trailer(dir)) {
547 		ret = ocfs2_check_dir_trailer(dir, tmp);
548 		if (ret) {
549 			if (!*bh)
550 				brelse(tmp);
551 			mlog_errno(ret);
552 			goto out;
553 		}
554 	}
555 
556 	if (!ret && !*bh)
557 		*bh = tmp;
558 out:
559 	return ret;
560 }
561 
562 static int ocfs2_validate_dx_root(struct super_block *sb,
563 				  struct buffer_head *bh)
564 {
565 	int ret;
566 	struct ocfs2_dx_root_block *dx_root;
567 
568 	BUG_ON(!buffer_uptodate(bh));
569 
570 	dx_root = (struct ocfs2_dx_root_block *) bh->b_data;
571 
572 	ret = ocfs2_validate_meta_ecc(sb, bh->b_data, &dx_root->dr_check);
573 	if (ret) {
574 		mlog(ML_ERROR,
575 		     "Checksum failed for dir index root block %llu\n",
576 		     (unsigned long long)bh->b_blocknr);
577 		return ret;
578 	}
579 
580 	if (!OCFS2_IS_VALID_DX_ROOT(dx_root)) {
581 		ret = ocfs2_error(sb,
582 				  "Dir Index Root # %llu has bad signature %.*s\n",
583 				  (unsigned long long)le64_to_cpu(dx_root->dr_blkno),
584 				  7, dx_root->dr_signature);
585 	}
586 
587 	return ret;
588 }
589 
590 static int ocfs2_read_dx_root(struct inode *dir, struct ocfs2_dinode *di,
591 			      struct buffer_head **dx_root_bh)
592 {
593 	int ret;
594 	u64 blkno = le64_to_cpu(di->i_dx_root);
595 	struct buffer_head *tmp = *dx_root_bh;
596 
597 	ret = ocfs2_read_block(INODE_CACHE(dir), blkno, &tmp,
598 			       ocfs2_validate_dx_root);
599 
600 	/* If ocfs2_read_block() got us a new bh, pass it up. */
601 	if (!ret && !*dx_root_bh)
602 		*dx_root_bh = tmp;
603 
604 	return ret;
605 }
606 
607 static int ocfs2_validate_dx_leaf(struct super_block *sb,
608 				  struct buffer_head *bh)
609 {
610 	int ret;
611 	struct ocfs2_dx_leaf *dx_leaf = (struct ocfs2_dx_leaf *)bh->b_data;
612 
613 	BUG_ON(!buffer_uptodate(bh));
614 
615 	ret = ocfs2_validate_meta_ecc(sb, bh->b_data, &dx_leaf->dl_check);
616 	if (ret) {
617 		mlog(ML_ERROR,
618 		     "Checksum failed for dir index leaf block %llu\n",
619 		     (unsigned long long)bh->b_blocknr);
620 		return ret;
621 	}
622 
623 	if (!OCFS2_IS_VALID_DX_LEAF(dx_leaf)) {
624 		ret = ocfs2_error(sb, "Dir Index Leaf has bad signature %.*s\n",
625 				  7, dx_leaf->dl_signature);
626 	}
627 
628 	return ret;
629 }
630 
631 static int ocfs2_read_dx_leaf(struct inode *dir, u64 blkno,
632 			      struct buffer_head **dx_leaf_bh)
633 {
634 	int ret;
635 	struct buffer_head *tmp = *dx_leaf_bh;
636 
637 	ret = ocfs2_read_block(INODE_CACHE(dir), blkno, &tmp,
638 			       ocfs2_validate_dx_leaf);
639 
640 	/* If ocfs2_read_block() got us a new bh, pass it up. */
641 	if (!ret && !*dx_leaf_bh)
642 		*dx_leaf_bh = tmp;
643 
644 	return ret;
645 }
646 
647 /*
648  * Read a series of dx_leaf blocks. This expects all buffer_head
649  * pointers to be NULL on function entry.
650  */
651 static int ocfs2_read_dx_leaves(struct inode *dir, u64 start, int num,
652 				struct buffer_head **dx_leaf_bhs)
653 {
654 	int ret;
655 
656 	ret = ocfs2_read_blocks(INODE_CACHE(dir), start, num, dx_leaf_bhs, 0,
657 				ocfs2_validate_dx_leaf);
658 	if (ret)
659 		mlog_errno(ret);
660 
661 	return ret;
662 }
663 
664 static struct buffer_head *ocfs2_find_entry_el(const char *name, int namelen,
665 					       struct inode *dir,
666 					       struct ocfs2_dir_entry **res_dir)
667 {
668 	struct super_block *sb;
669 	struct buffer_head *bh_use[NAMEI_RA_SIZE];
670 	struct buffer_head *bh, *ret = NULL;
671 	unsigned long start, block, b;
672 	int ra_max = 0;		/* Number of bh's in the readahead
673 				   buffer, bh_use[] */
674 	int ra_ptr = 0;		/* Current index into readahead
675 				   buffer */
676 	int num = 0;
677 	int nblocks, i;
678 
679 	sb = dir->i_sb;
680 
681 	nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
682 	start = OCFS2_I(dir)->ip_dir_start_lookup;
683 	if (start >= nblocks)
684 		start = 0;
685 	block = start;
686 
687 restart:
688 	do {
689 		/*
690 		 * We deal with the read-ahead logic here.
691 		 */
692 		if (ra_ptr >= ra_max) {
693 			/* Refill the readahead buffer */
694 			ra_ptr = 0;
695 			b = block;
696 			for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
697 				/*
698 				 * Terminate if we reach the end of the
699 				 * directory and must wrap, or if our
700 				 * search has finished at this block.
701 				 */
702 				if (b >= nblocks || (num && block == start)) {
703 					bh_use[ra_max] = NULL;
704 					break;
705 				}
706 				num++;
707 
708 				bh = NULL;
709 				ocfs2_read_dir_block(dir, b++, &bh,
710 							   OCFS2_BH_READAHEAD);
711 				bh_use[ra_max] = bh;
712 			}
713 		}
714 		if ((bh = bh_use[ra_ptr++]) == NULL)
715 			goto next;
716 		if (ocfs2_read_dir_block(dir, block, &bh, 0)) {
717 			/* read error, skip block & hope for the best.
718 			 * ocfs2_read_dir_block() has released the bh. */
719 			mlog(ML_ERROR, "reading directory %llu, "
720 				    "offset %lu\n",
721 				    (unsigned long long)OCFS2_I(dir)->ip_blkno,
722 				    block);
723 			goto next;
724 		}
725 		i = ocfs2_search_dirblock(bh, dir, name, namelen,
726 					  block << sb->s_blocksize_bits,
727 					  bh->b_data, sb->s_blocksize,
728 					  res_dir);
729 		if (i == 1) {
730 			OCFS2_I(dir)->ip_dir_start_lookup = block;
731 			ret = bh;
732 			goto cleanup_and_exit;
733 		} else {
734 			brelse(bh);
735 			if (i < 0)
736 				goto cleanup_and_exit;
737 		}
738 	next:
739 		if (++block >= nblocks)
740 			block = 0;
741 	} while (block != start);
742 
743 	/*
744 	 * If the directory has grown while we were searching, then
745 	 * search the last part of the directory before giving up.
746 	 */
747 	block = nblocks;
748 	nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
749 	if (block < nblocks) {
750 		start = 0;
751 		goto restart;
752 	}
753 
754 cleanup_and_exit:
755 	/* Clean up the read-ahead blocks */
756 	for (; ra_ptr < ra_max; ra_ptr++)
757 		brelse(bh_use[ra_ptr]);
758 
759 	trace_ocfs2_find_entry_el(ret);
760 	return ret;
761 }
762 
763 static int ocfs2_dx_dir_lookup_rec(struct inode *inode,
764 				   struct ocfs2_extent_list *el,
765 				   u32 major_hash,
766 				   u32 *ret_cpos,
767 				   u64 *ret_phys_blkno,
768 				   unsigned int *ret_clen)
769 {
770 	int ret = 0, i, found;
771 	struct buffer_head *eb_bh = NULL;
772 	struct ocfs2_extent_block *eb;
773 	struct ocfs2_extent_rec *rec = NULL;
774 
775 	if (el->l_tree_depth) {
776 		ret = ocfs2_find_leaf(INODE_CACHE(inode), el, major_hash,
777 				      &eb_bh);
778 		if (ret) {
779 			mlog_errno(ret);
780 			goto out;
781 		}
782 
783 		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
784 		el = &eb->h_list;
785 
786 		if (el->l_tree_depth) {
787 			ret = ocfs2_error(inode->i_sb,
788 					  "Inode %lu has non zero tree depth in btree tree block %llu\n",
789 					  inode->i_ino,
790 					  (unsigned long long)eb_bh->b_blocknr);
791 			goto out;
792 		}
793 	}
794 
795 	found = 0;
796 	for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
797 		rec = &el->l_recs[i];
798 
799 		if (le32_to_cpu(rec->e_cpos) <= major_hash) {
800 			found = 1;
801 			break;
802 		}
803 	}
804 
805 	if (!found) {
806 		ret = ocfs2_error(inode->i_sb,
807 				  "Inode %lu has bad extent record (%u, %u, 0) in btree\n",
808 				  inode->i_ino,
809 				  le32_to_cpu(rec->e_cpos),
810 				  ocfs2_rec_clusters(el, rec));
811 		goto out;
812 	}
813 
814 	if (ret_phys_blkno)
815 		*ret_phys_blkno = le64_to_cpu(rec->e_blkno);
816 	if (ret_cpos)
817 		*ret_cpos = le32_to_cpu(rec->e_cpos);
818 	if (ret_clen)
819 		*ret_clen = le16_to_cpu(rec->e_leaf_clusters);
820 
821 out:
822 	brelse(eb_bh);
823 	return ret;
824 }
825 
826 /*
827  * Returns the block index, from the start of the cluster which this
828  * hash belongs too.
829  */
830 static inline unsigned int __ocfs2_dx_dir_hash_idx(struct ocfs2_super *osb,
831 						   u32 minor_hash)
832 {
833 	return minor_hash & osb->osb_dx_mask;
834 }
835 
836 static inline unsigned int ocfs2_dx_dir_hash_idx(struct ocfs2_super *osb,
837 					  struct ocfs2_dx_hinfo *hinfo)
838 {
839 	return __ocfs2_dx_dir_hash_idx(osb, hinfo->minor_hash);
840 }
841 
842 static int ocfs2_dx_dir_lookup(struct inode *inode,
843 			       struct ocfs2_extent_list *el,
844 			       struct ocfs2_dx_hinfo *hinfo,
845 			       u32 *ret_cpos,
846 			       u64 *ret_phys_blkno)
847 {
848 	int ret = 0;
849 	unsigned int cend, clen;
850 	u32 cpos;
851 	u64 blkno;
852 	u32 name_hash = hinfo->major_hash;
853 
854 	ret = ocfs2_dx_dir_lookup_rec(inode, el, name_hash, &cpos, &blkno,
855 				      &clen);
856 	if (ret) {
857 		mlog_errno(ret);
858 		goto out;
859 	}
860 
861 	cend = cpos + clen;
862 	if (name_hash >= cend) {
863 		/* We want the last cluster */
864 		blkno += ocfs2_clusters_to_blocks(inode->i_sb, clen - 1);
865 		cpos += clen - 1;
866 	} else {
867 		blkno += ocfs2_clusters_to_blocks(inode->i_sb,
868 						  name_hash - cpos);
869 		cpos = name_hash;
870 	}
871 
872 	/*
873 	 * We now have the cluster which should hold our entry. To
874 	 * find the exact block from the start of the cluster to
875 	 * search, we take the lower bits of the hash.
876 	 */
877 	blkno += ocfs2_dx_dir_hash_idx(OCFS2_SB(inode->i_sb), hinfo);
878 
879 	if (ret_phys_blkno)
880 		*ret_phys_blkno = blkno;
881 	if (ret_cpos)
882 		*ret_cpos = cpos;
883 
884 out:
885 
886 	return ret;
887 }
888 
889 static int ocfs2_dx_dir_search(const char *name, int namelen,
890 			       struct inode *dir,
891 			       struct ocfs2_dx_root_block *dx_root,
892 			       struct ocfs2_dir_lookup_result *res)
893 {
894 	int ret, i, found;
895 	u64 phys;
896 	struct buffer_head *dx_leaf_bh = NULL;
897 	struct ocfs2_dx_leaf *dx_leaf;
898 	struct ocfs2_dx_entry *dx_entry = NULL;
899 	struct buffer_head *dir_ent_bh = NULL;
900 	struct ocfs2_dir_entry *dir_ent = NULL;
901 	struct ocfs2_dx_hinfo *hinfo = &res->dl_hinfo;
902 	struct ocfs2_extent_list *dr_el;
903 	struct ocfs2_dx_entry_list *entry_list;
904 
905 	ocfs2_dx_dir_name_hash(dir, name, namelen, &res->dl_hinfo);
906 
907 	if (ocfs2_dx_root_inline(dx_root)) {
908 		entry_list = &dx_root->dr_entries;
909 		goto search;
910 	}
911 
912 	dr_el = &dx_root->dr_list;
913 
914 	ret = ocfs2_dx_dir_lookup(dir, dr_el, hinfo, NULL, &phys);
915 	if (ret) {
916 		mlog_errno(ret);
917 		goto out;
918 	}
919 
920 	trace_ocfs2_dx_dir_search((unsigned long long)OCFS2_I(dir)->ip_blkno,
921 				  namelen, name, hinfo->major_hash,
922 				  hinfo->minor_hash, (unsigned long long)phys);
923 
924 	ret = ocfs2_read_dx_leaf(dir, phys, &dx_leaf_bh);
925 	if (ret) {
926 		mlog_errno(ret);
927 		goto out;
928 	}
929 
930 	dx_leaf = (struct ocfs2_dx_leaf *) dx_leaf_bh->b_data;
931 
932 	trace_ocfs2_dx_dir_search_leaf_info(
933 			le16_to_cpu(dx_leaf->dl_list.de_num_used),
934 			le16_to_cpu(dx_leaf->dl_list.de_count));
935 
936 	entry_list = &dx_leaf->dl_list;
937 
938 search:
939 	/*
940 	 * Empty leaf is legal, so no need to check for that.
941 	 */
942 	found = 0;
943 	for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) {
944 		dx_entry = &entry_list->de_entries[i];
945 
946 		if (hinfo->major_hash != le32_to_cpu(dx_entry->dx_major_hash)
947 		    || hinfo->minor_hash != le32_to_cpu(dx_entry->dx_minor_hash))
948 			continue;
949 
950 		/*
951 		 * Search unindexed leaf block now. We're not
952 		 * guaranteed to find anything.
953 		 */
954 		ret = ocfs2_read_dir_block_direct(dir,
955 					  le64_to_cpu(dx_entry->dx_dirent_blk),
956 					  &dir_ent_bh);
957 		if (ret) {
958 			mlog_errno(ret);
959 			goto out;
960 		}
961 
962 		/*
963 		 * XXX: We should check the unindexed block here,
964 		 * before using it.
965 		 */
966 
967 		found = ocfs2_search_dirblock(dir_ent_bh, dir, name, namelen,
968 					      0, dir_ent_bh->b_data,
969 					      dir->i_sb->s_blocksize, &dir_ent);
970 		if (found == 1)
971 			break;
972 
973 		if (found == -1) {
974 			/* This means we found a bad directory entry. */
975 			ret = -EIO;
976 			mlog_errno(ret);
977 			goto out;
978 		}
979 
980 		brelse(dir_ent_bh);
981 		dir_ent_bh = NULL;
982 	}
983 
984 	if (found <= 0) {
985 		ret = -ENOENT;
986 		goto out;
987 	}
988 
989 	res->dl_leaf_bh = dir_ent_bh;
990 	res->dl_entry = dir_ent;
991 	res->dl_dx_leaf_bh = dx_leaf_bh;
992 	res->dl_dx_entry = dx_entry;
993 
994 	ret = 0;
995 out:
996 	if (ret) {
997 		brelse(dx_leaf_bh);
998 		brelse(dir_ent_bh);
999 	}
1000 	return ret;
1001 }
1002 
1003 static int ocfs2_find_entry_dx(const char *name, int namelen,
1004 			       struct inode *dir,
1005 			       struct ocfs2_dir_lookup_result *lookup)
1006 {
1007 	int ret;
1008 	struct buffer_head *di_bh = NULL;
1009 	struct ocfs2_dinode *di;
1010 	struct buffer_head *dx_root_bh = NULL;
1011 	struct ocfs2_dx_root_block *dx_root;
1012 
1013 	ret = ocfs2_read_inode_block(dir, &di_bh);
1014 	if (ret) {
1015 		mlog_errno(ret);
1016 		goto out;
1017 	}
1018 
1019 	di = (struct ocfs2_dinode *)di_bh->b_data;
1020 
1021 	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
1022 	if (ret) {
1023 		mlog_errno(ret);
1024 		goto out;
1025 	}
1026 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
1027 
1028 	ret = ocfs2_dx_dir_search(name, namelen, dir, dx_root, lookup);
1029 	if (ret) {
1030 		if (ret != -ENOENT)
1031 			mlog_errno(ret);
1032 		goto out;
1033 	}
1034 
1035 	lookup->dl_dx_root_bh = dx_root_bh;
1036 	dx_root_bh = NULL;
1037 out:
1038 	brelse(di_bh);
1039 	brelse(dx_root_bh);
1040 	return ret;
1041 }
1042 
1043 /*
1044  * Try to find an entry of the provided name within 'dir'.
1045  *
1046  * If nothing was found, -ENOENT is returned. Otherwise, zero is
1047  * returned and the struct 'res' will contain information useful to
1048  * other directory manipulation functions.
1049  *
1050  * Caller can NOT assume anything about the contents of the
1051  * buffer_heads - they are passed back only so that it can be passed
1052  * into any one of the manipulation functions (add entry, delete
1053  * entry, etc). As an example, bh in the extent directory case is a
1054  * data block, in the inline-data case it actually points to an inode,
1055  * in the indexed directory case, multiple buffers are involved.
1056  */
1057 int ocfs2_find_entry(const char *name, int namelen,
1058 		     struct inode *dir, struct ocfs2_dir_lookup_result *lookup)
1059 {
1060 	struct buffer_head *bh;
1061 	struct ocfs2_dir_entry *res_dir = NULL;
1062 
1063 	if (ocfs2_dir_indexed(dir))
1064 		return ocfs2_find_entry_dx(name, namelen, dir, lookup);
1065 
1066 	/*
1067 	 * The unindexed dir code only uses part of the lookup
1068 	 * structure, so there's no reason to push it down further
1069 	 * than this.
1070 	 */
1071 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1072 		bh = ocfs2_find_entry_id(name, namelen, dir, &res_dir);
1073 	else
1074 		bh = ocfs2_find_entry_el(name, namelen, dir, &res_dir);
1075 
1076 	if (bh == NULL)
1077 		return -ENOENT;
1078 
1079 	lookup->dl_leaf_bh = bh;
1080 	lookup->dl_entry = res_dir;
1081 	return 0;
1082 }
1083 
1084 /*
1085  * Update inode number and type of a previously found directory entry.
1086  */
1087 int ocfs2_update_entry(struct inode *dir, handle_t *handle,
1088 		       struct ocfs2_dir_lookup_result *res,
1089 		       struct inode *new_entry_inode)
1090 {
1091 	int ret;
1092 	ocfs2_journal_access_func access = ocfs2_journal_access_db;
1093 	struct ocfs2_dir_entry *de = res->dl_entry;
1094 	struct buffer_head *de_bh = res->dl_leaf_bh;
1095 
1096 	/*
1097 	 * The same code works fine for both inline-data and extent
1098 	 * based directories, so no need to split this up.  The only
1099 	 * difference is the journal_access function.
1100 	 */
1101 
1102 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1103 		access = ocfs2_journal_access_di;
1104 
1105 	ret = access(handle, INODE_CACHE(dir), de_bh,
1106 		     OCFS2_JOURNAL_ACCESS_WRITE);
1107 	if (ret) {
1108 		mlog_errno(ret);
1109 		goto out;
1110 	}
1111 
1112 	de->inode = cpu_to_le64(OCFS2_I(new_entry_inode)->ip_blkno);
1113 	ocfs2_set_de_type(de, new_entry_inode->i_mode);
1114 
1115 	ocfs2_journal_dirty(handle, de_bh);
1116 
1117 out:
1118 	return ret;
1119 }
1120 
1121 /*
1122  * __ocfs2_delete_entry deletes a directory entry by merging it with the
1123  * previous entry
1124  */
1125 static int __ocfs2_delete_entry(handle_t *handle, struct inode *dir,
1126 				struct ocfs2_dir_entry *de_del,
1127 				struct buffer_head *bh, char *first_de,
1128 				unsigned int bytes)
1129 {
1130 	struct ocfs2_dir_entry *de, *pde;
1131 	int i, status = -ENOENT;
1132 	ocfs2_journal_access_func access = ocfs2_journal_access_db;
1133 
1134 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1135 		access = ocfs2_journal_access_di;
1136 
1137 	i = 0;
1138 	pde = NULL;
1139 	de = (struct ocfs2_dir_entry *) first_de;
1140 	while (i < bytes) {
1141 		if (!ocfs2_check_dir_entry(dir, de, bh, i)) {
1142 			status = -EIO;
1143 			mlog_errno(status);
1144 			goto bail;
1145 		}
1146 		if (de == de_del)  {
1147 			status = access(handle, INODE_CACHE(dir), bh,
1148 					OCFS2_JOURNAL_ACCESS_WRITE);
1149 			if (status < 0) {
1150 				status = -EIO;
1151 				mlog_errno(status);
1152 				goto bail;
1153 			}
1154 			if (pde)
1155 				le16_add_cpu(&pde->rec_len,
1156 						le16_to_cpu(de->rec_len));
1157 			de->inode = 0;
1158 			inode_inc_iversion(dir);
1159 			ocfs2_journal_dirty(handle, bh);
1160 			goto bail;
1161 		}
1162 		i += le16_to_cpu(de->rec_len);
1163 		pde = de;
1164 		de = (struct ocfs2_dir_entry *)((char *)de + le16_to_cpu(de->rec_len));
1165 	}
1166 bail:
1167 	return status;
1168 }
1169 
1170 static unsigned int ocfs2_figure_dirent_hole(struct ocfs2_dir_entry *de)
1171 {
1172 	unsigned int hole;
1173 
1174 	if (le64_to_cpu(de->inode) == 0)
1175 		hole = le16_to_cpu(de->rec_len);
1176 	else
1177 		hole = le16_to_cpu(de->rec_len) -
1178 			OCFS2_DIR_REC_LEN(de->name_len);
1179 
1180 	return hole;
1181 }
1182 
1183 static int ocfs2_find_max_rec_len(struct super_block *sb,
1184 				  struct buffer_head *dirblock_bh)
1185 {
1186 	int size, this_hole, largest_hole = 0;
1187 	char *trailer, *de_buf, *limit, *start = dirblock_bh->b_data;
1188 	struct ocfs2_dir_entry *de;
1189 
1190 	trailer = (char *)ocfs2_trailer_from_bh(dirblock_bh, sb);
1191 	size = ocfs2_dir_trailer_blk_off(sb);
1192 	limit = start + size;
1193 	de_buf = start;
1194 	de = (struct ocfs2_dir_entry *)de_buf;
1195 	do {
1196 		if (de_buf != trailer) {
1197 			this_hole = ocfs2_figure_dirent_hole(de);
1198 			if (this_hole > largest_hole)
1199 				largest_hole = this_hole;
1200 		}
1201 
1202 		de_buf += le16_to_cpu(de->rec_len);
1203 		de = (struct ocfs2_dir_entry *)de_buf;
1204 	} while (de_buf < limit);
1205 
1206 	if (largest_hole >= OCFS2_DIR_MIN_REC_LEN)
1207 		return largest_hole;
1208 	return 0;
1209 }
1210 
1211 static void ocfs2_dx_list_remove_entry(struct ocfs2_dx_entry_list *entry_list,
1212 				       int index)
1213 {
1214 	int num_used = le16_to_cpu(entry_list->de_num_used);
1215 
1216 	if (num_used == 1 || index == (num_used - 1))
1217 		goto clear;
1218 
1219 	memmove(&entry_list->de_entries[index],
1220 		&entry_list->de_entries[index + 1],
1221 		(num_used - index - 1)*sizeof(struct ocfs2_dx_entry));
1222 clear:
1223 	num_used--;
1224 	memset(&entry_list->de_entries[num_used], 0,
1225 	       sizeof(struct ocfs2_dx_entry));
1226 	entry_list->de_num_used = cpu_to_le16(num_used);
1227 }
1228 
1229 static int ocfs2_delete_entry_dx(handle_t *handle, struct inode *dir,
1230 				 struct ocfs2_dir_lookup_result *lookup)
1231 {
1232 	int ret, index, max_rec_len, add_to_free_list = 0;
1233 	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
1234 	struct buffer_head *leaf_bh = lookup->dl_leaf_bh;
1235 	struct ocfs2_dx_leaf *dx_leaf;
1236 	struct ocfs2_dx_entry *dx_entry = lookup->dl_dx_entry;
1237 	struct ocfs2_dir_block_trailer *trailer;
1238 	struct ocfs2_dx_root_block *dx_root;
1239 	struct ocfs2_dx_entry_list *entry_list;
1240 
1241 	/*
1242 	 * This function gets a bit messy because we might have to
1243 	 * modify the root block, regardless of whether the indexed
1244 	 * entries are stored inline.
1245 	 */
1246 
1247 	/*
1248 	 * *Only* set 'entry_list' here, based on where we're looking
1249 	 * for the indexed entries. Later, we might still want to
1250 	 * journal both blocks, based on free list state.
1251 	 */
1252 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
1253 	if (ocfs2_dx_root_inline(dx_root)) {
1254 		entry_list = &dx_root->dr_entries;
1255 	} else {
1256 		dx_leaf = (struct ocfs2_dx_leaf *) lookup->dl_dx_leaf_bh->b_data;
1257 		entry_list = &dx_leaf->dl_list;
1258 	}
1259 
1260 	/* Neither of these are a disk corruption - that should have
1261 	 * been caught by lookup, before we got here. */
1262 	BUG_ON(le16_to_cpu(entry_list->de_count) <= 0);
1263 	BUG_ON(le16_to_cpu(entry_list->de_num_used) <= 0);
1264 
1265 	index = (char *)dx_entry - (char *)entry_list->de_entries;
1266 	index /= sizeof(*dx_entry);
1267 
1268 	if (index >= le16_to_cpu(entry_list->de_num_used)) {
1269 		mlog(ML_ERROR, "Dir %llu: Bad dx_entry ptr idx %d, (%p, %p)\n",
1270 		     (unsigned long long)OCFS2_I(dir)->ip_blkno, index,
1271 		     entry_list, dx_entry);
1272 		return -EIO;
1273 	}
1274 
1275 	/*
1276 	 * We know that removal of this dirent will leave enough room
1277 	 * for a new one, so add this block to the free list if it
1278 	 * isn't already there.
1279 	 */
1280 	trailer = ocfs2_trailer_from_bh(leaf_bh, dir->i_sb);
1281 	if (trailer->db_free_rec_len == 0)
1282 		add_to_free_list = 1;
1283 
1284 	/*
1285 	 * Add the block holding our index into the journal before
1286 	 * removing the unindexed entry. If we get an error return
1287 	 * from __ocfs2_delete_entry(), then it hasn't removed the
1288 	 * entry yet. Likewise, successful return means we *must*
1289 	 * remove the indexed entry.
1290 	 *
1291 	 * We're also careful to journal the root tree block here as
1292 	 * the entry count needs to be updated. Also, we might be
1293 	 * adding to the start of the free list.
1294 	 */
1295 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
1296 				      OCFS2_JOURNAL_ACCESS_WRITE);
1297 	if (ret) {
1298 		mlog_errno(ret);
1299 		goto out;
1300 	}
1301 
1302 	if (!ocfs2_dx_root_inline(dx_root)) {
1303 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
1304 					      lookup->dl_dx_leaf_bh,
1305 					      OCFS2_JOURNAL_ACCESS_WRITE);
1306 		if (ret) {
1307 			mlog_errno(ret);
1308 			goto out;
1309 		}
1310 	}
1311 
1312 	trace_ocfs2_delete_entry_dx((unsigned long long)OCFS2_I(dir)->ip_blkno,
1313 				    index);
1314 
1315 	ret = __ocfs2_delete_entry(handle, dir, lookup->dl_entry,
1316 				   leaf_bh, leaf_bh->b_data, leaf_bh->b_size);
1317 	if (ret) {
1318 		mlog_errno(ret);
1319 		goto out;
1320 	}
1321 
1322 	max_rec_len = ocfs2_find_max_rec_len(dir->i_sb, leaf_bh);
1323 	trailer->db_free_rec_len = cpu_to_le16(max_rec_len);
1324 	if (add_to_free_list) {
1325 		trailer->db_free_next = dx_root->dr_free_blk;
1326 		dx_root->dr_free_blk = cpu_to_le64(leaf_bh->b_blocknr);
1327 		ocfs2_journal_dirty(handle, dx_root_bh);
1328 	}
1329 
1330 	/* leaf_bh was journal_accessed for us in __ocfs2_delete_entry */
1331 	ocfs2_journal_dirty(handle, leaf_bh);
1332 
1333 	le32_add_cpu(&dx_root->dr_num_entries, -1);
1334 	ocfs2_journal_dirty(handle, dx_root_bh);
1335 
1336 	ocfs2_dx_list_remove_entry(entry_list, index);
1337 
1338 	if (!ocfs2_dx_root_inline(dx_root))
1339 		ocfs2_journal_dirty(handle, lookup->dl_dx_leaf_bh);
1340 
1341 out:
1342 	return ret;
1343 }
1344 
1345 static inline int ocfs2_delete_entry_id(handle_t *handle,
1346 					struct inode *dir,
1347 					struct ocfs2_dir_entry *de_del,
1348 					struct buffer_head *bh)
1349 {
1350 	int ret;
1351 	struct buffer_head *di_bh = NULL;
1352 	struct ocfs2_dinode *di;
1353 	struct ocfs2_inline_data *data;
1354 
1355 	ret = ocfs2_read_inode_block(dir, &di_bh);
1356 	if (ret) {
1357 		mlog_errno(ret);
1358 		goto out;
1359 	}
1360 
1361 	di = (struct ocfs2_dinode *)di_bh->b_data;
1362 	data = &di->id2.i_data;
1363 
1364 	ret = __ocfs2_delete_entry(handle, dir, de_del, bh, data->id_data,
1365 				   i_size_read(dir));
1366 
1367 	brelse(di_bh);
1368 out:
1369 	return ret;
1370 }
1371 
1372 static inline int ocfs2_delete_entry_el(handle_t *handle,
1373 					struct inode *dir,
1374 					struct ocfs2_dir_entry *de_del,
1375 					struct buffer_head *bh)
1376 {
1377 	return __ocfs2_delete_entry(handle, dir, de_del, bh, bh->b_data,
1378 				    bh->b_size);
1379 }
1380 
1381 /*
1382  * Delete a directory entry. Hide the details of directory
1383  * implementation from the caller.
1384  */
1385 int ocfs2_delete_entry(handle_t *handle,
1386 		       struct inode *dir,
1387 		       struct ocfs2_dir_lookup_result *res)
1388 {
1389 	if (ocfs2_dir_indexed(dir))
1390 		return ocfs2_delete_entry_dx(handle, dir, res);
1391 
1392 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1393 		return ocfs2_delete_entry_id(handle, dir, res->dl_entry,
1394 					     res->dl_leaf_bh);
1395 
1396 	return ocfs2_delete_entry_el(handle, dir, res->dl_entry,
1397 				     res->dl_leaf_bh);
1398 }
1399 
1400 /*
1401  * Check whether 'de' has enough room to hold an entry of
1402  * 'new_rec_len' bytes.
1403  */
1404 static inline int ocfs2_dirent_would_fit(struct ocfs2_dir_entry *de,
1405 					 unsigned int new_rec_len)
1406 {
1407 	unsigned int de_really_used;
1408 
1409 	/* Check whether this is an empty record with enough space */
1410 	if (le64_to_cpu(de->inode) == 0 &&
1411 	    le16_to_cpu(de->rec_len) >= new_rec_len)
1412 		return 1;
1413 
1414 	/*
1415 	 * Record might have free space at the end which we can
1416 	 * use.
1417 	 */
1418 	de_really_used = OCFS2_DIR_REC_LEN(de->name_len);
1419 	if (le16_to_cpu(de->rec_len) >= (de_really_used + new_rec_len))
1420 	    return 1;
1421 
1422 	return 0;
1423 }
1424 
1425 static void ocfs2_dx_dir_leaf_insert_tail(struct ocfs2_dx_leaf *dx_leaf,
1426 					  struct ocfs2_dx_entry *dx_new_entry)
1427 {
1428 	int i;
1429 
1430 	i = le16_to_cpu(dx_leaf->dl_list.de_num_used);
1431 	dx_leaf->dl_list.de_entries[i] = *dx_new_entry;
1432 
1433 	le16_add_cpu(&dx_leaf->dl_list.de_num_used, 1);
1434 }
1435 
1436 static void ocfs2_dx_entry_list_insert(struct ocfs2_dx_entry_list *entry_list,
1437 				       struct ocfs2_dx_hinfo *hinfo,
1438 				       u64 dirent_blk)
1439 {
1440 	int i;
1441 	struct ocfs2_dx_entry *dx_entry;
1442 
1443 	i = le16_to_cpu(entry_list->de_num_used);
1444 	dx_entry = &entry_list->de_entries[i];
1445 
1446 	memset(dx_entry, 0, sizeof(*dx_entry));
1447 	dx_entry->dx_major_hash = cpu_to_le32(hinfo->major_hash);
1448 	dx_entry->dx_minor_hash = cpu_to_le32(hinfo->minor_hash);
1449 	dx_entry->dx_dirent_blk = cpu_to_le64(dirent_blk);
1450 
1451 	le16_add_cpu(&entry_list->de_num_used, 1);
1452 }
1453 
1454 static int __ocfs2_dx_dir_leaf_insert(struct inode *dir, handle_t *handle,
1455 				      struct ocfs2_dx_hinfo *hinfo,
1456 				      u64 dirent_blk,
1457 				      struct buffer_head *dx_leaf_bh)
1458 {
1459 	int ret;
1460 	struct ocfs2_dx_leaf *dx_leaf;
1461 
1462 	ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), dx_leaf_bh,
1463 				      OCFS2_JOURNAL_ACCESS_WRITE);
1464 	if (ret) {
1465 		mlog_errno(ret);
1466 		goto out;
1467 	}
1468 
1469 	dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
1470 	ocfs2_dx_entry_list_insert(&dx_leaf->dl_list, hinfo, dirent_blk);
1471 	ocfs2_journal_dirty(handle, dx_leaf_bh);
1472 
1473 out:
1474 	return ret;
1475 }
1476 
1477 static void ocfs2_dx_inline_root_insert(struct inode *dir, handle_t *handle,
1478 					struct ocfs2_dx_hinfo *hinfo,
1479 					u64 dirent_blk,
1480 					struct ocfs2_dx_root_block *dx_root)
1481 {
1482 	ocfs2_dx_entry_list_insert(&dx_root->dr_entries, hinfo, dirent_blk);
1483 }
1484 
1485 static int ocfs2_dx_dir_insert(struct inode *dir, handle_t *handle,
1486 			       struct ocfs2_dir_lookup_result *lookup)
1487 {
1488 	int ret = 0;
1489 	struct ocfs2_dx_root_block *dx_root;
1490 	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
1491 
1492 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
1493 				      OCFS2_JOURNAL_ACCESS_WRITE);
1494 	if (ret) {
1495 		mlog_errno(ret);
1496 		goto out;
1497 	}
1498 
1499 	dx_root = (struct ocfs2_dx_root_block *)lookup->dl_dx_root_bh->b_data;
1500 	if (ocfs2_dx_root_inline(dx_root)) {
1501 		ocfs2_dx_inline_root_insert(dir, handle,
1502 					    &lookup->dl_hinfo,
1503 					    lookup->dl_leaf_bh->b_blocknr,
1504 					    dx_root);
1505 	} else {
1506 		ret = __ocfs2_dx_dir_leaf_insert(dir, handle, &lookup->dl_hinfo,
1507 						 lookup->dl_leaf_bh->b_blocknr,
1508 						 lookup->dl_dx_leaf_bh);
1509 		if (ret)
1510 			goto out;
1511 	}
1512 
1513 	le32_add_cpu(&dx_root->dr_num_entries, 1);
1514 	ocfs2_journal_dirty(handle, dx_root_bh);
1515 
1516 out:
1517 	return ret;
1518 }
1519 
1520 static void ocfs2_remove_block_from_free_list(struct inode *dir,
1521 				       handle_t *handle,
1522 				       struct ocfs2_dir_lookup_result *lookup)
1523 {
1524 	struct ocfs2_dir_block_trailer *trailer, *prev;
1525 	struct ocfs2_dx_root_block *dx_root;
1526 	struct buffer_head *bh;
1527 
1528 	trailer = ocfs2_trailer_from_bh(lookup->dl_leaf_bh, dir->i_sb);
1529 
1530 	if (ocfs2_free_list_at_root(lookup)) {
1531 		bh = lookup->dl_dx_root_bh;
1532 		dx_root = (struct ocfs2_dx_root_block *)bh->b_data;
1533 		dx_root->dr_free_blk = trailer->db_free_next;
1534 	} else {
1535 		bh = lookup->dl_prev_leaf_bh;
1536 		prev = ocfs2_trailer_from_bh(bh, dir->i_sb);
1537 		prev->db_free_next = trailer->db_free_next;
1538 	}
1539 
1540 	trailer->db_free_rec_len = cpu_to_le16(0);
1541 	trailer->db_free_next = cpu_to_le64(0);
1542 
1543 	ocfs2_journal_dirty(handle, bh);
1544 	ocfs2_journal_dirty(handle, lookup->dl_leaf_bh);
1545 }
1546 
1547 /*
1548  * This expects that a journal write has been reserved on
1549  * lookup->dl_prev_leaf_bh or lookup->dl_dx_root_bh
1550  */
1551 static void ocfs2_recalc_free_list(struct inode *dir, handle_t *handle,
1552 				   struct ocfs2_dir_lookup_result *lookup)
1553 {
1554 	int max_rec_len;
1555 	struct ocfs2_dir_block_trailer *trailer;
1556 
1557 	/* Walk dl_leaf_bh to figure out what the new free rec_len is. */
1558 	max_rec_len = ocfs2_find_max_rec_len(dir->i_sb, lookup->dl_leaf_bh);
1559 	if (max_rec_len) {
1560 		/*
1561 		 * There's still room in this block, so no need to remove it
1562 		 * from the free list. In this case, we just want to update
1563 		 * the rec len accounting.
1564 		 */
1565 		trailer = ocfs2_trailer_from_bh(lookup->dl_leaf_bh, dir->i_sb);
1566 		trailer->db_free_rec_len = cpu_to_le16(max_rec_len);
1567 		ocfs2_journal_dirty(handle, lookup->dl_leaf_bh);
1568 	} else {
1569 		ocfs2_remove_block_from_free_list(dir, handle, lookup);
1570 	}
1571 }
1572 
1573 /* we don't always have a dentry for what we want to add, so people
1574  * like orphan dir can call this instead.
1575  *
1576  * The lookup context must have been filled from
1577  * ocfs2_prepare_dir_for_insert.
1578  */
1579 int __ocfs2_add_entry(handle_t *handle,
1580 		      struct inode *dir,
1581 		      const char *name, int namelen,
1582 		      struct inode *inode, u64 blkno,
1583 		      struct buffer_head *parent_fe_bh,
1584 		      struct ocfs2_dir_lookup_result *lookup)
1585 {
1586 	unsigned long offset;
1587 	unsigned short rec_len;
1588 	struct ocfs2_dir_entry *de, *de1;
1589 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_fe_bh->b_data;
1590 	struct super_block *sb = dir->i_sb;
1591 	int retval;
1592 	unsigned int size = sb->s_blocksize;
1593 	struct buffer_head *insert_bh = lookup->dl_leaf_bh;
1594 	char *data_start = insert_bh->b_data;
1595 
1596 	if (!namelen)
1597 		return -EINVAL;
1598 
1599 	if (ocfs2_dir_indexed(dir)) {
1600 		struct buffer_head *bh;
1601 
1602 		/*
1603 		 * An indexed dir may require that we update the free space
1604 		 * list. Reserve a write to the previous node in the list so
1605 		 * that we don't fail later.
1606 		 *
1607 		 * XXX: This can be either a dx_root_block, or an unindexed
1608 		 * directory tree leaf block.
1609 		 */
1610 		if (ocfs2_free_list_at_root(lookup)) {
1611 			bh = lookup->dl_dx_root_bh;
1612 			retval = ocfs2_journal_access_dr(handle,
1613 						 INODE_CACHE(dir), bh,
1614 						 OCFS2_JOURNAL_ACCESS_WRITE);
1615 		} else {
1616 			bh = lookup->dl_prev_leaf_bh;
1617 			retval = ocfs2_journal_access_db(handle,
1618 						 INODE_CACHE(dir), bh,
1619 						 OCFS2_JOURNAL_ACCESS_WRITE);
1620 		}
1621 		if (retval) {
1622 			mlog_errno(retval);
1623 			return retval;
1624 		}
1625 	} else if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1626 		data_start = di->id2.i_data.id_data;
1627 		size = i_size_read(dir);
1628 
1629 		BUG_ON(insert_bh != parent_fe_bh);
1630 	}
1631 
1632 	rec_len = OCFS2_DIR_REC_LEN(namelen);
1633 	offset = 0;
1634 	de = (struct ocfs2_dir_entry *) data_start;
1635 	while (1) {
1636 		BUG_ON((char *)de >= (size + data_start));
1637 
1638 		/* These checks should've already been passed by the
1639 		 * prepare function, but I guess we can leave them
1640 		 * here anyway. */
1641 		if (!ocfs2_check_dir_entry(dir, de, insert_bh, offset)) {
1642 			retval = -ENOENT;
1643 			goto bail;
1644 		}
1645 		if (ocfs2_match(namelen, name, de)) {
1646 			retval = -EEXIST;
1647 			goto bail;
1648 		}
1649 
1650 		/* We're guaranteed that we should have space, so we
1651 		 * can't possibly have hit the trailer...right? */
1652 		mlog_bug_on_msg(ocfs2_skip_dir_trailer(dir, de, offset, size),
1653 				"Hit dir trailer trying to insert %.*s "
1654 			        "(namelen %d) into directory %llu.  "
1655 				"offset is %lu, trailer offset is %d\n",
1656 				namelen, name, namelen,
1657 				(unsigned long long)parent_fe_bh->b_blocknr,
1658 				offset, ocfs2_dir_trailer_blk_off(dir->i_sb));
1659 
1660 		if (ocfs2_dirent_would_fit(de, rec_len)) {
1661 			dir->i_mtime = dir->i_ctime = current_time(dir);
1662 			retval = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
1663 			if (retval < 0) {
1664 				mlog_errno(retval);
1665 				goto bail;
1666 			}
1667 
1668 			if (insert_bh == parent_fe_bh)
1669 				retval = ocfs2_journal_access_di(handle,
1670 								 INODE_CACHE(dir),
1671 								 insert_bh,
1672 								 OCFS2_JOURNAL_ACCESS_WRITE);
1673 			else {
1674 				retval = ocfs2_journal_access_db(handle,
1675 								 INODE_CACHE(dir),
1676 								 insert_bh,
1677 					      OCFS2_JOURNAL_ACCESS_WRITE);
1678 
1679 				if (!retval && ocfs2_dir_indexed(dir))
1680 					retval = ocfs2_dx_dir_insert(dir,
1681 								handle,
1682 								lookup);
1683 			}
1684 
1685 			if (retval) {
1686 				mlog_errno(retval);
1687 				goto bail;
1688 			}
1689 
1690 			/* By now the buffer is marked for journaling */
1691 			offset += le16_to_cpu(de->rec_len);
1692 			if (le64_to_cpu(de->inode)) {
1693 				de1 = (struct ocfs2_dir_entry *)((char *) de +
1694 					OCFS2_DIR_REC_LEN(de->name_len));
1695 				de1->rec_len =
1696 					cpu_to_le16(le16_to_cpu(de->rec_len) -
1697 					OCFS2_DIR_REC_LEN(de->name_len));
1698 				de->rec_len = cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
1699 				de = de1;
1700 			}
1701 			de->file_type = FT_UNKNOWN;
1702 			if (blkno) {
1703 				de->inode = cpu_to_le64(blkno);
1704 				ocfs2_set_de_type(de, inode->i_mode);
1705 			} else
1706 				de->inode = 0;
1707 			de->name_len = namelen;
1708 			memcpy(de->name, name, namelen);
1709 
1710 			if (ocfs2_dir_indexed(dir))
1711 				ocfs2_recalc_free_list(dir, handle, lookup);
1712 
1713 			inode_inc_iversion(dir);
1714 			ocfs2_journal_dirty(handle, insert_bh);
1715 			retval = 0;
1716 			goto bail;
1717 		}
1718 
1719 		offset += le16_to_cpu(de->rec_len);
1720 		de = (struct ocfs2_dir_entry *) ((char *) de + le16_to_cpu(de->rec_len));
1721 	}
1722 
1723 	/* when you think about it, the assert above should prevent us
1724 	 * from ever getting here. */
1725 	retval = -ENOSPC;
1726 bail:
1727 	if (retval)
1728 		mlog_errno(retval);
1729 
1730 	return retval;
1731 }
1732 
1733 static int ocfs2_dir_foreach_blk_id(struct inode *inode,
1734 				    u64 *f_version,
1735 				    struct dir_context *ctx)
1736 {
1737 	int ret, i;
1738 	unsigned long offset = ctx->pos;
1739 	struct buffer_head *di_bh = NULL;
1740 	struct ocfs2_dinode *di;
1741 	struct ocfs2_inline_data *data;
1742 	struct ocfs2_dir_entry *de;
1743 
1744 	ret = ocfs2_read_inode_block(inode, &di_bh);
1745 	if (ret) {
1746 		mlog(ML_ERROR, "Unable to read inode block for dir %llu\n",
1747 		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
1748 		goto out;
1749 	}
1750 
1751 	di = (struct ocfs2_dinode *)di_bh->b_data;
1752 	data = &di->id2.i_data;
1753 
1754 	while (ctx->pos < i_size_read(inode)) {
1755 		/* If the dir block has changed since the last call to
1756 		 * readdir(2), then we might be pointing to an invalid
1757 		 * dirent right now.  Scan from the start of the block
1758 		 * to make sure. */
1759 		if (!inode_eq_iversion(inode, *f_version)) {
1760 			for (i = 0; i < i_size_read(inode) && i < offset; ) {
1761 				de = (struct ocfs2_dir_entry *)
1762 					(data->id_data + i);
1763 				/* It's too expensive to do a full
1764 				 * dirent test each time round this
1765 				 * loop, but we do have to test at
1766 				 * least that it is non-zero.  A
1767 				 * failure will be detected in the
1768 				 * dirent test below. */
1769 				if (le16_to_cpu(de->rec_len) <
1770 				    OCFS2_DIR_REC_LEN(1))
1771 					break;
1772 				i += le16_to_cpu(de->rec_len);
1773 			}
1774 			ctx->pos = offset = i;
1775 			*f_version = inode_query_iversion(inode);
1776 		}
1777 
1778 		de = (struct ocfs2_dir_entry *) (data->id_data + ctx->pos);
1779 		if (!ocfs2_check_dir_entry(inode, de, di_bh, ctx->pos)) {
1780 			/* On error, skip the f_pos to the end. */
1781 			ctx->pos = i_size_read(inode);
1782 			break;
1783 		}
1784 		offset += le16_to_cpu(de->rec_len);
1785 		if (le64_to_cpu(de->inode)) {
1786 			if (!dir_emit(ctx, de->name, de->name_len,
1787 				      le64_to_cpu(de->inode),
1788 				      fs_ftype_to_dtype(de->file_type)))
1789 				goto out;
1790 		}
1791 		ctx->pos += le16_to_cpu(de->rec_len);
1792 	}
1793 out:
1794 	brelse(di_bh);
1795 	return 0;
1796 }
1797 
1798 /*
1799  * NOTE: This function can be called against unindexed directories,
1800  * and indexed ones.
1801  */
1802 static int ocfs2_dir_foreach_blk_el(struct inode *inode,
1803 				    u64 *f_version,
1804 				    struct dir_context *ctx,
1805 				    bool persist)
1806 {
1807 	unsigned long offset, blk, last_ra_blk = 0;
1808 	int i;
1809 	struct buffer_head * bh, * tmp;
1810 	struct ocfs2_dir_entry * de;
1811 	struct super_block * sb = inode->i_sb;
1812 	unsigned int ra_sectors = 16;
1813 	int stored = 0;
1814 
1815 	bh = NULL;
1816 
1817 	offset = ctx->pos & (sb->s_blocksize - 1);
1818 
1819 	while (ctx->pos < i_size_read(inode)) {
1820 		blk = ctx->pos >> sb->s_blocksize_bits;
1821 		if (ocfs2_read_dir_block(inode, blk, &bh, 0)) {
1822 			/* Skip the corrupt dirblock and keep trying */
1823 			ctx->pos += sb->s_blocksize - offset;
1824 			continue;
1825 		}
1826 
1827 		/* The idea here is to begin with 8k read-ahead and to stay
1828 		 * 4k ahead of our current position.
1829 		 *
1830 		 * TODO: Use the pagecache for this. We just need to
1831 		 * make sure it's cluster-safe... */
1832 		if (!last_ra_blk
1833 		    || (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) {
1834 			for (i = ra_sectors >> (sb->s_blocksize_bits - 9);
1835 			     i > 0; i--) {
1836 				tmp = NULL;
1837 				if (!ocfs2_read_dir_block(inode, ++blk, &tmp,
1838 							  OCFS2_BH_READAHEAD))
1839 					brelse(tmp);
1840 			}
1841 			last_ra_blk = blk;
1842 			ra_sectors = 8;
1843 		}
1844 
1845 		/* If the dir block has changed since the last call to
1846 		 * readdir(2), then we might be pointing to an invalid
1847 		 * dirent right now.  Scan from the start of the block
1848 		 * to make sure. */
1849 		if (!inode_eq_iversion(inode, *f_version)) {
1850 			for (i = 0; i < sb->s_blocksize && i < offset; ) {
1851 				de = (struct ocfs2_dir_entry *) (bh->b_data + i);
1852 				/* It's too expensive to do a full
1853 				 * dirent test each time round this
1854 				 * loop, but we do have to test at
1855 				 * least that it is non-zero.  A
1856 				 * failure will be detected in the
1857 				 * dirent test below. */
1858 				if (le16_to_cpu(de->rec_len) <
1859 				    OCFS2_DIR_REC_LEN(1))
1860 					break;
1861 				i += le16_to_cpu(de->rec_len);
1862 			}
1863 			offset = i;
1864 			ctx->pos = (ctx->pos & ~(sb->s_blocksize - 1))
1865 				| offset;
1866 			*f_version = inode_query_iversion(inode);
1867 		}
1868 
1869 		while (ctx->pos < i_size_read(inode)
1870 		       && offset < sb->s_blocksize) {
1871 			de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
1872 			if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
1873 				/* On error, skip the f_pos to the
1874 				   next block. */
1875 				ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
1876 				break;
1877 			}
1878 			if (le64_to_cpu(de->inode)) {
1879 				if (!dir_emit(ctx, de->name,
1880 						de->name_len,
1881 						le64_to_cpu(de->inode),
1882 					fs_ftype_to_dtype(de->file_type))) {
1883 					brelse(bh);
1884 					return 0;
1885 				}
1886 				stored++;
1887 			}
1888 			offset += le16_to_cpu(de->rec_len);
1889 			ctx->pos += le16_to_cpu(de->rec_len);
1890 		}
1891 		offset = 0;
1892 		brelse(bh);
1893 		bh = NULL;
1894 		if (!persist && stored)
1895 			break;
1896 	}
1897 	return 0;
1898 }
1899 
1900 static int ocfs2_dir_foreach_blk(struct inode *inode, u64 *f_version,
1901 				 struct dir_context *ctx,
1902 				 bool persist)
1903 {
1904 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1905 		return ocfs2_dir_foreach_blk_id(inode, f_version, ctx);
1906 	return ocfs2_dir_foreach_blk_el(inode, f_version, ctx, persist);
1907 }
1908 
1909 /*
1910  * This is intended to be called from inside other kernel functions,
1911  * so we fake some arguments.
1912  */
1913 int ocfs2_dir_foreach(struct inode *inode, struct dir_context *ctx)
1914 {
1915 	u64 version = inode_query_iversion(inode);
1916 	ocfs2_dir_foreach_blk(inode, &version, ctx, true);
1917 	return 0;
1918 }
1919 
1920 /*
1921  * ocfs2_readdir()
1922  *
1923  */
1924 int ocfs2_readdir(struct file *file, struct dir_context *ctx)
1925 {
1926 	int error = 0;
1927 	struct inode *inode = file_inode(file);
1928 	int lock_level = 0;
1929 
1930 	trace_ocfs2_readdir((unsigned long long)OCFS2_I(inode)->ip_blkno);
1931 
1932 	error = ocfs2_inode_lock_atime(inode, file->f_path.mnt, &lock_level, 1);
1933 	if (lock_level && error >= 0) {
1934 		/* We release EX lock which used to update atime
1935 		 * and get PR lock again to reduce contention
1936 		 * on commonly accessed directories. */
1937 		ocfs2_inode_unlock(inode, 1);
1938 		lock_level = 0;
1939 		error = ocfs2_inode_lock(inode, NULL, 0);
1940 	}
1941 	if (error < 0) {
1942 		if (error != -ENOENT)
1943 			mlog_errno(error);
1944 		/* we haven't got any yet, so propagate the error. */
1945 		goto bail_nolock;
1946 	}
1947 
1948 	error = ocfs2_dir_foreach_blk(inode, &file->f_version, ctx, false);
1949 
1950 	ocfs2_inode_unlock(inode, lock_level);
1951 	if (error)
1952 		mlog_errno(error);
1953 
1954 bail_nolock:
1955 
1956 	return error;
1957 }
1958 
1959 /*
1960  * NOTE: this should always be called with parent dir i_mutex taken.
1961  */
1962 int ocfs2_find_files_on_disk(const char *name,
1963 			     int namelen,
1964 			     u64 *blkno,
1965 			     struct inode *inode,
1966 			     struct ocfs2_dir_lookup_result *lookup)
1967 {
1968 	int status = -ENOENT;
1969 
1970 	trace_ocfs2_find_files_on_disk(namelen, name, blkno,
1971 				(unsigned long long)OCFS2_I(inode)->ip_blkno);
1972 
1973 	status = ocfs2_find_entry(name, namelen, inode, lookup);
1974 	if (status)
1975 		goto leave;
1976 
1977 	*blkno = le64_to_cpu(lookup->dl_entry->inode);
1978 
1979 	status = 0;
1980 leave:
1981 
1982 	return status;
1983 }
1984 
1985 /*
1986  * Convenience function for callers which just want the block number
1987  * mapped to a name and don't require the full dirent info, etc.
1988  */
1989 int ocfs2_lookup_ino_from_name(struct inode *dir, const char *name,
1990 			       int namelen, u64 *blkno)
1991 {
1992 	int ret;
1993 	struct ocfs2_dir_lookup_result lookup = { NULL, };
1994 
1995 	ret = ocfs2_find_files_on_disk(name, namelen, blkno, dir, &lookup);
1996 	ocfs2_free_dir_lookup_result(&lookup);
1997 
1998 	return ret;
1999 }
2000 
2001 /* Check for a name within a directory.
2002  *
2003  * Return 0 if the name does not exist
2004  * Return -EEXIST if the directory contains the name
2005  *
2006  * Callers should have i_mutex + a cluster lock on dir
2007  */
2008 int ocfs2_check_dir_for_entry(struct inode *dir,
2009 			      const char *name,
2010 			      int namelen)
2011 {
2012 	int ret = 0;
2013 	struct ocfs2_dir_lookup_result lookup = { NULL, };
2014 
2015 	trace_ocfs2_check_dir_for_entry(
2016 		(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
2017 
2018 	if (ocfs2_find_entry(name, namelen, dir, &lookup) == 0) {
2019 		ret = -EEXIST;
2020 		mlog_errno(ret);
2021 	}
2022 
2023 	ocfs2_free_dir_lookup_result(&lookup);
2024 
2025 	return ret;
2026 }
2027 
2028 struct ocfs2_empty_dir_priv {
2029 	struct dir_context ctx;
2030 	unsigned seen_dot;
2031 	unsigned seen_dot_dot;
2032 	unsigned seen_other;
2033 	unsigned dx_dir;
2034 };
2035 static int ocfs2_empty_dir_filldir(struct dir_context *ctx, const char *name,
2036 				   int name_len, loff_t pos, u64 ino,
2037 				   unsigned type)
2038 {
2039 	struct ocfs2_empty_dir_priv *p =
2040 		container_of(ctx, struct ocfs2_empty_dir_priv, ctx);
2041 
2042 	/*
2043 	 * Check the positions of "." and ".." records to be sure
2044 	 * they're in the correct place.
2045 	 *
2046 	 * Indexed directories don't need to proceed past the first
2047 	 * two entries, so we end the scan after seeing '..'. Despite
2048 	 * that, we allow the scan to proceed In the event that we
2049 	 * have a corrupted indexed directory (no dot or dot dot
2050 	 * entries). This allows us to double check for existing
2051 	 * entries which might not have been found in the index.
2052 	 */
2053 	if (name_len == 1 && !strncmp(".", name, 1) && pos == 0) {
2054 		p->seen_dot = 1;
2055 		return 0;
2056 	}
2057 
2058 	if (name_len == 2 && !strncmp("..", name, 2) &&
2059 	    pos == OCFS2_DIR_REC_LEN(1)) {
2060 		p->seen_dot_dot = 1;
2061 
2062 		if (p->dx_dir && p->seen_dot)
2063 			return 1;
2064 
2065 		return 0;
2066 	}
2067 
2068 	p->seen_other = 1;
2069 	return 1;
2070 }
2071 
2072 static int ocfs2_empty_dir_dx(struct inode *inode,
2073 			      struct ocfs2_empty_dir_priv *priv)
2074 {
2075 	int ret;
2076 	struct buffer_head *di_bh = NULL;
2077 	struct buffer_head *dx_root_bh = NULL;
2078 	struct ocfs2_dinode *di;
2079 	struct ocfs2_dx_root_block *dx_root;
2080 
2081 	priv->dx_dir = 1;
2082 
2083 	ret = ocfs2_read_inode_block(inode, &di_bh);
2084 	if (ret) {
2085 		mlog_errno(ret);
2086 		goto out;
2087 	}
2088 	di = (struct ocfs2_dinode *)di_bh->b_data;
2089 
2090 	ret = ocfs2_read_dx_root(inode, di, &dx_root_bh);
2091 	if (ret) {
2092 		mlog_errno(ret);
2093 		goto out;
2094 	}
2095 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2096 
2097 	if (le32_to_cpu(dx_root->dr_num_entries) != 2)
2098 		priv->seen_other = 1;
2099 
2100 out:
2101 	brelse(di_bh);
2102 	brelse(dx_root_bh);
2103 	return ret;
2104 }
2105 
2106 /*
2107  * routine to check that the specified directory is empty (for rmdir)
2108  *
2109  * Returns 1 if dir is empty, zero otherwise.
2110  *
2111  * XXX: This is a performance problem for unindexed directories.
2112  */
2113 int ocfs2_empty_dir(struct inode *inode)
2114 {
2115 	int ret;
2116 	struct ocfs2_empty_dir_priv priv = {
2117 		.ctx.actor = ocfs2_empty_dir_filldir,
2118 	};
2119 
2120 	if (ocfs2_dir_indexed(inode)) {
2121 		ret = ocfs2_empty_dir_dx(inode, &priv);
2122 		if (ret)
2123 			mlog_errno(ret);
2124 		/*
2125 		 * We still run ocfs2_dir_foreach to get the checks
2126 		 * for "." and "..".
2127 		 */
2128 	}
2129 
2130 	ret = ocfs2_dir_foreach(inode, &priv.ctx);
2131 	if (ret)
2132 		mlog_errno(ret);
2133 
2134 	if (!priv.seen_dot || !priv.seen_dot_dot) {
2135 		mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
2136 		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
2137 		/*
2138 		 * XXX: Is it really safe to allow an unlink to continue?
2139 		 */
2140 		return 1;
2141 	}
2142 
2143 	return !priv.seen_other;
2144 }
2145 
2146 /*
2147  * Fills "." and ".." dirents in a new directory block. Returns dirent for
2148  * "..", which might be used during creation of a directory with a trailing
2149  * header. It is otherwise safe to ignore the return code.
2150  */
2151 static struct ocfs2_dir_entry *ocfs2_fill_initial_dirents(struct inode *inode,
2152 							  struct inode *parent,
2153 							  char *start,
2154 							  unsigned int size)
2155 {
2156 	struct ocfs2_dir_entry *de = (struct ocfs2_dir_entry *)start;
2157 
2158 	de->inode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
2159 	de->name_len = 1;
2160 	de->rec_len =
2161 		cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
2162 	strcpy(de->name, ".");
2163 	ocfs2_set_de_type(de, S_IFDIR);
2164 
2165 	de = (struct ocfs2_dir_entry *) ((char *)de + le16_to_cpu(de->rec_len));
2166 	de->inode = cpu_to_le64(OCFS2_I(parent)->ip_blkno);
2167 	de->rec_len = cpu_to_le16(size - OCFS2_DIR_REC_LEN(1));
2168 	de->name_len = 2;
2169 	strcpy(de->name, "..");
2170 	ocfs2_set_de_type(de, S_IFDIR);
2171 
2172 	return de;
2173 }
2174 
2175 /*
2176  * This works together with code in ocfs2_mknod_locked() which sets
2177  * the inline-data flag and initializes the inline-data section.
2178  */
2179 static int ocfs2_fill_new_dir_id(struct ocfs2_super *osb,
2180 				 handle_t *handle,
2181 				 struct inode *parent,
2182 				 struct inode *inode,
2183 				 struct buffer_head *di_bh)
2184 {
2185 	int ret;
2186 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
2187 	struct ocfs2_inline_data *data = &di->id2.i_data;
2188 	unsigned int size = le16_to_cpu(data->id_count);
2189 
2190 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
2191 				      OCFS2_JOURNAL_ACCESS_WRITE);
2192 	if (ret) {
2193 		mlog_errno(ret);
2194 		goto out;
2195 	}
2196 
2197 	ocfs2_fill_initial_dirents(inode, parent, data->id_data, size);
2198 	ocfs2_journal_dirty(handle, di_bh);
2199 
2200 	i_size_write(inode, size);
2201 	set_nlink(inode, 2);
2202 	inode->i_blocks = ocfs2_inode_sector_count(inode);
2203 
2204 	ret = ocfs2_mark_inode_dirty(handle, inode, di_bh);
2205 	if (ret < 0)
2206 		mlog_errno(ret);
2207 
2208 out:
2209 	return ret;
2210 }
2211 
2212 static int ocfs2_fill_new_dir_el(struct ocfs2_super *osb,
2213 				 handle_t *handle,
2214 				 struct inode *parent,
2215 				 struct inode *inode,
2216 				 struct buffer_head *fe_bh,
2217 				 struct ocfs2_alloc_context *data_ac,
2218 				 struct buffer_head **ret_new_bh)
2219 {
2220 	int status;
2221 	unsigned int size = osb->sb->s_blocksize;
2222 	struct buffer_head *new_bh = NULL;
2223 	struct ocfs2_dir_entry *de;
2224 
2225 	if (ocfs2_new_dir_wants_trailer(inode))
2226 		size = ocfs2_dir_trailer_blk_off(parent->i_sb);
2227 
2228 	status = ocfs2_do_extend_dir(osb->sb, handle, inode, fe_bh,
2229 				     data_ac, NULL, &new_bh);
2230 	if (status < 0) {
2231 		mlog_errno(status);
2232 		goto bail;
2233 	}
2234 
2235 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), new_bh);
2236 
2237 	status = ocfs2_journal_access_db(handle, INODE_CACHE(inode), new_bh,
2238 					 OCFS2_JOURNAL_ACCESS_CREATE);
2239 	if (status < 0) {
2240 		mlog_errno(status);
2241 		goto bail;
2242 	}
2243 	memset(new_bh->b_data, 0, osb->sb->s_blocksize);
2244 
2245 	de = ocfs2_fill_initial_dirents(inode, parent, new_bh->b_data, size);
2246 	if (ocfs2_new_dir_wants_trailer(inode)) {
2247 		int size = le16_to_cpu(de->rec_len);
2248 
2249 		/*
2250 		 * Figure out the size of the hole left over after
2251 		 * insertion of '.' and '..'. The trailer wants this
2252 		 * information.
2253 		 */
2254 		size -= OCFS2_DIR_REC_LEN(2);
2255 		size -= sizeof(struct ocfs2_dir_block_trailer);
2256 
2257 		ocfs2_init_dir_trailer(inode, new_bh, size);
2258 	}
2259 
2260 	ocfs2_journal_dirty(handle, new_bh);
2261 
2262 	i_size_write(inode, inode->i_sb->s_blocksize);
2263 	set_nlink(inode, 2);
2264 	inode->i_blocks = ocfs2_inode_sector_count(inode);
2265 	status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
2266 	if (status < 0) {
2267 		mlog_errno(status);
2268 		goto bail;
2269 	}
2270 
2271 	status = 0;
2272 	if (ret_new_bh) {
2273 		*ret_new_bh = new_bh;
2274 		new_bh = NULL;
2275 	}
2276 bail:
2277 	brelse(new_bh);
2278 
2279 	return status;
2280 }
2281 
2282 static int ocfs2_dx_dir_attach_index(struct ocfs2_super *osb,
2283 				     handle_t *handle, struct inode *dir,
2284 				     struct buffer_head *di_bh,
2285 				     struct buffer_head *dirdata_bh,
2286 				     struct ocfs2_alloc_context *meta_ac,
2287 				     int dx_inline, u32 num_entries,
2288 				     struct buffer_head **ret_dx_root_bh)
2289 {
2290 	int ret;
2291 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
2292 	u16 dr_suballoc_bit;
2293 	u64 suballoc_loc, dr_blkno;
2294 	unsigned int num_bits;
2295 	struct buffer_head *dx_root_bh = NULL;
2296 	struct ocfs2_dx_root_block *dx_root;
2297 	struct ocfs2_dir_block_trailer *trailer =
2298 		ocfs2_trailer_from_bh(dirdata_bh, dir->i_sb);
2299 
2300 	ret = ocfs2_claim_metadata(handle, meta_ac, 1, &suballoc_loc,
2301 				   &dr_suballoc_bit, &num_bits, &dr_blkno);
2302 	if (ret) {
2303 		mlog_errno(ret);
2304 		goto out;
2305 	}
2306 
2307 	trace_ocfs2_dx_dir_attach_index(
2308 				(unsigned long long)OCFS2_I(dir)->ip_blkno,
2309 				(unsigned long long)dr_blkno);
2310 
2311 	dx_root_bh = sb_getblk(osb->sb, dr_blkno);
2312 	if (dx_root_bh == NULL) {
2313 		ret = -ENOMEM;
2314 		goto out;
2315 	}
2316 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), dx_root_bh);
2317 
2318 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
2319 				      OCFS2_JOURNAL_ACCESS_CREATE);
2320 	if (ret < 0) {
2321 		mlog_errno(ret);
2322 		goto out;
2323 	}
2324 
2325 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2326 	memset(dx_root, 0, osb->sb->s_blocksize);
2327 	strcpy(dx_root->dr_signature, OCFS2_DX_ROOT_SIGNATURE);
2328 	dx_root->dr_suballoc_slot = cpu_to_le16(meta_ac->ac_alloc_slot);
2329 	dx_root->dr_suballoc_loc = cpu_to_le64(suballoc_loc);
2330 	dx_root->dr_suballoc_bit = cpu_to_le16(dr_suballoc_bit);
2331 	dx_root->dr_fs_generation = cpu_to_le32(osb->fs_generation);
2332 	dx_root->dr_blkno = cpu_to_le64(dr_blkno);
2333 	dx_root->dr_dir_blkno = cpu_to_le64(OCFS2_I(dir)->ip_blkno);
2334 	dx_root->dr_num_entries = cpu_to_le32(num_entries);
2335 	if (le16_to_cpu(trailer->db_free_rec_len))
2336 		dx_root->dr_free_blk = cpu_to_le64(dirdata_bh->b_blocknr);
2337 	else
2338 		dx_root->dr_free_blk = cpu_to_le64(0);
2339 
2340 	if (dx_inline) {
2341 		dx_root->dr_flags |= OCFS2_DX_FLAG_INLINE;
2342 		dx_root->dr_entries.de_count =
2343 			cpu_to_le16(ocfs2_dx_entries_per_root(osb->sb));
2344 	} else {
2345 		dx_root->dr_list.l_count =
2346 			cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
2347 	}
2348 	ocfs2_journal_dirty(handle, dx_root_bh);
2349 
2350 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
2351 				      OCFS2_JOURNAL_ACCESS_CREATE);
2352 	if (ret) {
2353 		mlog_errno(ret);
2354 		goto out;
2355 	}
2356 
2357 	di->i_dx_root = cpu_to_le64(dr_blkno);
2358 
2359 	spin_lock(&OCFS2_I(dir)->ip_lock);
2360 	OCFS2_I(dir)->ip_dyn_features |= OCFS2_INDEXED_DIR_FL;
2361 	di->i_dyn_features = cpu_to_le16(OCFS2_I(dir)->ip_dyn_features);
2362 	spin_unlock(&OCFS2_I(dir)->ip_lock);
2363 
2364 	ocfs2_journal_dirty(handle, di_bh);
2365 
2366 	*ret_dx_root_bh = dx_root_bh;
2367 	dx_root_bh = NULL;
2368 
2369 out:
2370 	brelse(dx_root_bh);
2371 	return ret;
2372 }
2373 
2374 static int ocfs2_dx_dir_format_cluster(struct ocfs2_super *osb,
2375 				       handle_t *handle, struct inode *dir,
2376 				       struct buffer_head **dx_leaves,
2377 				       int num_dx_leaves, u64 start_blk)
2378 {
2379 	int ret, i;
2380 	struct ocfs2_dx_leaf *dx_leaf;
2381 	struct buffer_head *bh;
2382 
2383 	for (i = 0; i < num_dx_leaves; i++) {
2384 		bh = sb_getblk(osb->sb, start_blk + i);
2385 		if (bh == NULL) {
2386 			ret = -ENOMEM;
2387 			goto out;
2388 		}
2389 		dx_leaves[i] = bh;
2390 
2391 		ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), bh);
2392 
2393 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), bh,
2394 					      OCFS2_JOURNAL_ACCESS_CREATE);
2395 		if (ret < 0) {
2396 			mlog_errno(ret);
2397 			goto out;
2398 		}
2399 
2400 		dx_leaf = (struct ocfs2_dx_leaf *) bh->b_data;
2401 
2402 		memset(dx_leaf, 0, osb->sb->s_blocksize);
2403 		strcpy(dx_leaf->dl_signature, OCFS2_DX_LEAF_SIGNATURE);
2404 		dx_leaf->dl_fs_generation = cpu_to_le32(osb->fs_generation);
2405 		dx_leaf->dl_blkno = cpu_to_le64(bh->b_blocknr);
2406 		dx_leaf->dl_list.de_count =
2407 			cpu_to_le16(ocfs2_dx_entries_per_leaf(osb->sb));
2408 
2409 		trace_ocfs2_dx_dir_format_cluster(
2410 				(unsigned long long)OCFS2_I(dir)->ip_blkno,
2411 				(unsigned long long)bh->b_blocknr,
2412 				le16_to_cpu(dx_leaf->dl_list.de_count));
2413 
2414 		ocfs2_journal_dirty(handle, bh);
2415 	}
2416 
2417 	ret = 0;
2418 out:
2419 	return ret;
2420 }
2421 
2422 /*
2423  * Allocates and formats a new cluster for use in an indexed dir
2424  * leaf. This version will not do the extent insert, so that it can be
2425  * used by operations which need careful ordering.
2426  */
2427 static int __ocfs2_dx_dir_new_cluster(struct inode *dir,
2428 				      u32 cpos, handle_t *handle,
2429 				      struct ocfs2_alloc_context *data_ac,
2430 				      struct buffer_head **dx_leaves,
2431 				      int num_dx_leaves, u64 *ret_phys_blkno)
2432 {
2433 	int ret;
2434 	u32 phys, num;
2435 	u64 phys_blkno;
2436 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
2437 
2438 	/*
2439 	 * XXX: For create, this should claim cluster for the index
2440 	 * *before* the unindexed insert so that we have a better
2441 	 * chance of contiguousness as the directory grows in number
2442 	 * of entries.
2443 	 */
2444 	ret = __ocfs2_claim_clusters(handle, data_ac, 1, 1, &phys, &num);
2445 	if (ret) {
2446 		mlog_errno(ret);
2447 		goto out;
2448 	}
2449 
2450 	/*
2451 	 * Format the new cluster first. That way, we're inserting
2452 	 * valid data.
2453 	 */
2454 	phys_blkno = ocfs2_clusters_to_blocks(osb->sb, phys);
2455 	ret = ocfs2_dx_dir_format_cluster(osb, handle, dir, dx_leaves,
2456 					  num_dx_leaves, phys_blkno);
2457 	if (ret) {
2458 		mlog_errno(ret);
2459 		goto out;
2460 	}
2461 
2462 	*ret_phys_blkno = phys_blkno;
2463 out:
2464 	return ret;
2465 }
2466 
2467 static int ocfs2_dx_dir_new_cluster(struct inode *dir,
2468 				    struct ocfs2_extent_tree *et,
2469 				    u32 cpos, handle_t *handle,
2470 				    struct ocfs2_alloc_context *data_ac,
2471 				    struct ocfs2_alloc_context *meta_ac,
2472 				    struct buffer_head **dx_leaves,
2473 				    int num_dx_leaves)
2474 {
2475 	int ret;
2476 	u64 phys_blkno;
2477 
2478 	ret = __ocfs2_dx_dir_new_cluster(dir, cpos, handle, data_ac, dx_leaves,
2479 					 num_dx_leaves, &phys_blkno);
2480 	if (ret) {
2481 		mlog_errno(ret);
2482 		goto out;
2483 	}
2484 
2485 	ret = ocfs2_insert_extent(handle, et, cpos, phys_blkno, 1, 0,
2486 				  meta_ac);
2487 	if (ret)
2488 		mlog_errno(ret);
2489 out:
2490 	return ret;
2491 }
2492 
2493 static struct buffer_head **ocfs2_dx_dir_kmalloc_leaves(struct super_block *sb,
2494 							int *ret_num_leaves)
2495 {
2496 	int num_dx_leaves = ocfs2_clusters_to_blocks(sb, 1);
2497 	struct buffer_head **dx_leaves;
2498 
2499 	dx_leaves = kcalloc(num_dx_leaves, sizeof(struct buffer_head *),
2500 			    GFP_NOFS);
2501 	if (dx_leaves && ret_num_leaves)
2502 		*ret_num_leaves = num_dx_leaves;
2503 
2504 	return dx_leaves;
2505 }
2506 
2507 static int ocfs2_fill_new_dir_dx(struct ocfs2_super *osb,
2508 				 handle_t *handle,
2509 				 struct inode *parent,
2510 				 struct inode *inode,
2511 				 struct buffer_head *di_bh,
2512 				 struct ocfs2_alloc_context *data_ac,
2513 				 struct ocfs2_alloc_context *meta_ac)
2514 {
2515 	int ret;
2516 	struct buffer_head *leaf_bh = NULL;
2517 	struct buffer_head *dx_root_bh = NULL;
2518 	struct ocfs2_dx_hinfo hinfo;
2519 	struct ocfs2_dx_root_block *dx_root;
2520 	struct ocfs2_dx_entry_list *entry_list;
2521 
2522 	/*
2523 	 * Our strategy is to create the directory as though it were
2524 	 * unindexed, then add the index block. This works with very
2525 	 * little complication since the state of a new directory is a
2526 	 * very well known quantity.
2527 	 *
2528 	 * Essentially, we have two dirents ("." and ".."), in the 1st
2529 	 * block which need indexing. These are easily inserted into
2530 	 * the index block.
2531 	 */
2532 
2533 	ret = ocfs2_fill_new_dir_el(osb, handle, parent, inode, di_bh,
2534 				    data_ac, &leaf_bh);
2535 	if (ret) {
2536 		mlog_errno(ret);
2537 		goto out;
2538 	}
2539 
2540 	ret = ocfs2_dx_dir_attach_index(osb, handle, inode, di_bh, leaf_bh,
2541 					meta_ac, 1, 2, &dx_root_bh);
2542 	if (ret) {
2543 		mlog_errno(ret);
2544 		goto out;
2545 	}
2546 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2547 	entry_list = &dx_root->dr_entries;
2548 
2549 	/* Buffer has been journaled for us by ocfs2_dx_dir_attach_index */
2550 	ocfs2_dx_dir_name_hash(inode, ".", 1, &hinfo);
2551 	ocfs2_dx_entry_list_insert(entry_list, &hinfo, leaf_bh->b_blocknr);
2552 
2553 	ocfs2_dx_dir_name_hash(inode, "..", 2, &hinfo);
2554 	ocfs2_dx_entry_list_insert(entry_list, &hinfo, leaf_bh->b_blocknr);
2555 
2556 out:
2557 	brelse(dx_root_bh);
2558 	brelse(leaf_bh);
2559 	return ret;
2560 }
2561 
2562 int ocfs2_fill_new_dir(struct ocfs2_super *osb,
2563 		       handle_t *handle,
2564 		       struct inode *parent,
2565 		       struct inode *inode,
2566 		       struct buffer_head *fe_bh,
2567 		       struct ocfs2_alloc_context *data_ac,
2568 		       struct ocfs2_alloc_context *meta_ac)
2569 
2570 {
2571 	BUG_ON(!ocfs2_supports_inline_data(osb) && data_ac == NULL);
2572 
2573 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
2574 		return ocfs2_fill_new_dir_id(osb, handle, parent, inode, fe_bh);
2575 
2576 	if (ocfs2_supports_indexed_dirs(osb))
2577 		return ocfs2_fill_new_dir_dx(osb, handle, parent, inode, fe_bh,
2578 					     data_ac, meta_ac);
2579 
2580 	return ocfs2_fill_new_dir_el(osb, handle, parent, inode, fe_bh,
2581 				     data_ac, NULL);
2582 }
2583 
2584 static int ocfs2_dx_dir_index_block(struct inode *dir,
2585 				    handle_t *handle,
2586 				    struct buffer_head **dx_leaves,
2587 				    int num_dx_leaves,
2588 				    u32 *num_dx_entries,
2589 				    struct buffer_head *dirent_bh)
2590 {
2591 	int ret = 0, namelen, i;
2592 	char *de_buf, *limit;
2593 	struct ocfs2_dir_entry *de;
2594 	struct buffer_head *dx_leaf_bh;
2595 	struct ocfs2_dx_hinfo hinfo;
2596 	u64 dirent_blk = dirent_bh->b_blocknr;
2597 
2598 	de_buf = dirent_bh->b_data;
2599 	limit = de_buf + dir->i_sb->s_blocksize;
2600 
2601 	while (de_buf < limit) {
2602 		de = (struct ocfs2_dir_entry *)de_buf;
2603 
2604 		namelen = de->name_len;
2605 		if (!namelen || !de->inode)
2606 			goto inc;
2607 
2608 		ocfs2_dx_dir_name_hash(dir, de->name, namelen, &hinfo);
2609 
2610 		i = ocfs2_dx_dir_hash_idx(OCFS2_SB(dir->i_sb), &hinfo);
2611 		dx_leaf_bh = dx_leaves[i];
2612 
2613 		ret = __ocfs2_dx_dir_leaf_insert(dir, handle, &hinfo,
2614 						 dirent_blk, dx_leaf_bh);
2615 		if (ret) {
2616 			mlog_errno(ret);
2617 			goto out;
2618 		}
2619 
2620 		*num_dx_entries = *num_dx_entries + 1;
2621 
2622 inc:
2623 		de_buf += le16_to_cpu(de->rec_len);
2624 	}
2625 
2626 out:
2627 	return ret;
2628 }
2629 
2630 /*
2631  * XXX: This expects dx_root_bh to already be part of the transaction.
2632  */
2633 static void ocfs2_dx_dir_index_root_block(struct inode *dir,
2634 					 struct buffer_head *dx_root_bh,
2635 					 struct buffer_head *dirent_bh)
2636 {
2637 	char *de_buf, *limit;
2638 	struct ocfs2_dx_root_block *dx_root;
2639 	struct ocfs2_dir_entry *de;
2640 	struct ocfs2_dx_hinfo hinfo;
2641 	u64 dirent_blk = dirent_bh->b_blocknr;
2642 
2643 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2644 
2645 	de_buf = dirent_bh->b_data;
2646 	limit = de_buf + dir->i_sb->s_blocksize;
2647 
2648 	while (de_buf < limit) {
2649 		de = (struct ocfs2_dir_entry *)de_buf;
2650 
2651 		if (!de->name_len || !de->inode)
2652 			goto inc;
2653 
2654 		ocfs2_dx_dir_name_hash(dir, de->name, de->name_len, &hinfo);
2655 
2656 		trace_ocfs2_dx_dir_index_root_block(
2657 				(unsigned long long)dir->i_ino,
2658 				hinfo.major_hash, hinfo.minor_hash,
2659 				de->name_len, de->name,
2660 				le16_to_cpu(dx_root->dr_entries.de_num_used));
2661 
2662 		ocfs2_dx_entry_list_insert(&dx_root->dr_entries, &hinfo,
2663 					   dirent_blk);
2664 
2665 		le32_add_cpu(&dx_root->dr_num_entries, 1);
2666 inc:
2667 		de_buf += le16_to_cpu(de->rec_len);
2668 	}
2669 }
2670 
2671 /*
2672  * Count the number of inline directory entries in di_bh and compare
2673  * them against the number of entries we can hold in an inline dx root
2674  * block.
2675  */
2676 static int ocfs2_new_dx_should_be_inline(struct inode *dir,
2677 					 struct buffer_head *di_bh)
2678 {
2679 	int dirent_count = 0;
2680 	char *de_buf, *limit;
2681 	struct ocfs2_dir_entry *de;
2682 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
2683 
2684 	de_buf = di->id2.i_data.id_data;
2685 	limit = de_buf + i_size_read(dir);
2686 
2687 	while (de_buf < limit) {
2688 		de = (struct ocfs2_dir_entry *)de_buf;
2689 
2690 		if (de->name_len && de->inode)
2691 			dirent_count++;
2692 
2693 		de_buf += le16_to_cpu(de->rec_len);
2694 	}
2695 
2696 	/* We are careful to leave room for one extra record. */
2697 	return dirent_count < ocfs2_dx_entries_per_root(dir->i_sb);
2698 }
2699 
2700 /*
2701  * Expand rec_len of the rightmost dirent in a directory block so that it
2702  * contains the end of our valid space for dirents. We do this during
2703  * expansion from an inline directory to one with extents. The first dir block
2704  * in that case is taken from the inline data portion of the inode block.
2705  *
2706  * This will also return the largest amount of contiguous space for a dirent
2707  * in the block. That value is *not* necessarily the last dirent, even after
2708  * expansion. The directory indexing code wants this value for free space
2709  * accounting. We do this here since we're already walking the entire dir
2710  * block.
2711  *
2712  * We add the dir trailer if this filesystem wants it.
2713  */
2714 static unsigned int ocfs2_expand_last_dirent(char *start, unsigned int old_size,
2715 					     struct inode *dir)
2716 {
2717 	struct super_block *sb = dir->i_sb;
2718 	struct ocfs2_dir_entry *de;
2719 	struct ocfs2_dir_entry *prev_de;
2720 	char *de_buf, *limit;
2721 	unsigned int new_size = sb->s_blocksize;
2722 	unsigned int bytes, this_hole;
2723 	unsigned int largest_hole = 0;
2724 
2725 	if (ocfs2_new_dir_wants_trailer(dir))
2726 		new_size = ocfs2_dir_trailer_blk_off(sb);
2727 
2728 	bytes = new_size - old_size;
2729 
2730 	limit = start + old_size;
2731 	de_buf = start;
2732 	de = (struct ocfs2_dir_entry *)de_buf;
2733 	do {
2734 		this_hole = ocfs2_figure_dirent_hole(de);
2735 		if (this_hole > largest_hole)
2736 			largest_hole = this_hole;
2737 
2738 		prev_de = de;
2739 		de_buf += le16_to_cpu(de->rec_len);
2740 		de = (struct ocfs2_dir_entry *)de_buf;
2741 	} while (de_buf < limit);
2742 
2743 	le16_add_cpu(&prev_de->rec_len, bytes);
2744 
2745 	/* We need to double check this after modification of the final
2746 	 * dirent. */
2747 	this_hole = ocfs2_figure_dirent_hole(prev_de);
2748 	if (this_hole > largest_hole)
2749 		largest_hole = this_hole;
2750 
2751 	if (largest_hole >= OCFS2_DIR_MIN_REC_LEN)
2752 		return largest_hole;
2753 	return 0;
2754 }
2755 
2756 /*
2757  * We allocate enough clusters to fulfill "blocks_wanted", but set
2758  * i_size to exactly one block. Ocfs2_extend_dir() will handle the
2759  * rest automatically for us.
2760  *
2761  * *first_block_bh is a pointer to the 1st data block allocated to the
2762  *  directory.
2763  */
2764 static int ocfs2_expand_inline_dir(struct inode *dir, struct buffer_head *di_bh,
2765 				   unsigned int blocks_wanted,
2766 				   struct ocfs2_dir_lookup_result *lookup,
2767 				   struct buffer_head **first_block_bh)
2768 {
2769 	u32 alloc, dx_alloc, bit_off, len, num_dx_entries = 0;
2770 	struct super_block *sb = dir->i_sb;
2771 	int ret, i, num_dx_leaves = 0, dx_inline = 0,
2772 		credits = ocfs2_inline_to_extents_credits(sb);
2773 	u64 dx_insert_blkno, blkno,
2774 		bytes = blocks_wanted << sb->s_blocksize_bits;
2775 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
2776 	struct ocfs2_inode_info *oi = OCFS2_I(dir);
2777 	struct ocfs2_alloc_context *data_ac = NULL;
2778 	struct ocfs2_alloc_context *meta_ac = NULL;
2779 	struct buffer_head *dirdata_bh = NULL;
2780 	struct buffer_head *dx_root_bh = NULL;
2781 	struct buffer_head **dx_leaves = NULL;
2782 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
2783 	handle_t *handle;
2784 	struct ocfs2_extent_tree et;
2785 	struct ocfs2_extent_tree dx_et;
2786 	int did_quota = 0, bytes_allocated = 0;
2787 
2788 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(dir), di_bh);
2789 
2790 	alloc = ocfs2_clusters_for_bytes(sb, bytes);
2791 	dx_alloc = 0;
2792 
2793 	down_write(&oi->ip_alloc_sem);
2794 
2795 	if (ocfs2_supports_indexed_dirs(osb)) {
2796 		credits += ocfs2_add_dir_index_credits(sb);
2797 
2798 		dx_inline = ocfs2_new_dx_should_be_inline(dir, di_bh);
2799 		if (!dx_inline) {
2800 			/* Add one more cluster for an index leaf */
2801 			dx_alloc++;
2802 			dx_leaves = ocfs2_dx_dir_kmalloc_leaves(sb,
2803 								&num_dx_leaves);
2804 			if (!dx_leaves) {
2805 				ret = -ENOMEM;
2806 				mlog_errno(ret);
2807 				goto out;
2808 			}
2809 		}
2810 
2811 		/* This gets us the dx_root */
2812 		ret = ocfs2_reserve_new_metadata_blocks(osb, 1, &meta_ac);
2813 		if (ret) {
2814 			mlog_errno(ret);
2815 			goto out;
2816 		}
2817 	}
2818 
2819 	/*
2820 	 * We should never need more than 2 clusters for the unindexed
2821 	 * tree - maximum dirent size is far less than one block. In
2822 	 * fact, the only time we'd need more than one cluster is if
2823 	 * blocksize == clustersize and the dirent won't fit in the
2824 	 * extra space that the expansion to a single block gives. As
2825 	 * of today, that only happens on 4k/4k file systems.
2826 	 */
2827 	BUG_ON(alloc > 2);
2828 
2829 	ret = ocfs2_reserve_clusters(osb, alloc + dx_alloc, &data_ac);
2830 	if (ret) {
2831 		mlog_errno(ret);
2832 		goto out;
2833 	}
2834 
2835 	/*
2836 	 * Prepare for worst case allocation scenario of two separate
2837 	 * extents in the unindexed tree.
2838 	 */
2839 	if (alloc == 2)
2840 		credits += OCFS2_SUBALLOC_ALLOC;
2841 
2842 	handle = ocfs2_start_trans(osb, credits);
2843 	if (IS_ERR(handle)) {
2844 		ret = PTR_ERR(handle);
2845 		mlog_errno(ret);
2846 		goto out;
2847 	}
2848 
2849 	ret = dquot_alloc_space_nodirty(dir,
2850 		ocfs2_clusters_to_bytes(osb->sb, alloc + dx_alloc));
2851 	if (ret)
2852 		goto out_commit;
2853 	did_quota = 1;
2854 
2855 	if (ocfs2_supports_indexed_dirs(osb) && !dx_inline) {
2856 		/*
2857 		 * Allocate our index cluster first, to maximize the
2858 		 * possibility that unindexed leaves grow
2859 		 * contiguously.
2860 		 */
2861 		ret = __ocfs2_dx_dir_new_cluster(dir, 0, handle, data_ac,
2862 						 dx_leaves, num_dx_leaves,
2863 						 &dx_insert_blkno);
2864 		if (ret) {
2865 			mlog_errno(ret);
2866 			goto out_commit;
2867 		}
2868 		bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
2869 	}
2870 
2871 	/*
2872 	 * Try to claim as many clusters as the bitmap can give though
2873 	 * if we only get one now, that's enough to continue. The rest
2874 	 * will be claimed after the conversion to extents.
2875 	 */
2876 	if (ocfs2_dir_resv_allowed(osb))
2877 		data_ac->ac_resv = &oi->ip_la_data_resv;
2878 	ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off, &len);
2879 	if (ret) {
2880 		mlog_errno(ret);
2881 		goto out_commit;
2882 	}
2883 	bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
2884 
2885 	/*
2886 	 * Operations are carefully ordered so that we set up the new
2887 	 * data block first. The conversion from inline data to
2888 	 * extents follows.
2889 	 */
2890 	blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
2891 	dirdata_bh = sb_getblk(sb, blkno);
2892 	if (!dirdata_bh) {
2893 		ret = -ENOMEM;
2894 		mlog_errno(ret);
2895 		goto out_commit;
2896 	}
2897 
2898 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), dirdata_bh);
2899 
2900 	ret = ocfs2_journal_access_db(handle, INODE_CACHE(dir), dirdata_bh,
2901 				      OCFS2_JOURNAL_ACCESS_CREATE);
2902 	if (ret) {
2903 		mlog_errno(ret);
2904 		goto out_commit;
2905 	}
2906 
2907 	memcpy(dirdata_bh->b_data, di->id2.i_data.id_data, i_size_read(dir));
2908 	memset(dirdata_bh->b_data + i_size_read(dir), 0,
2909 	       sb->s_blocksize - i_size_read(dir));
2910 	i = ocfs2_expand_last_dirent(dirdata_bh->b_data, i_size_read(dir), dir);
2911 	if (ocfs2_new_dir_wants_trailer(dir)) {
2912 		/*
2913 		 * Prepare the dir trailer up front. It will otherwise look
2914 		 * like a valid dirent. Even if inserting the index fails
2915 		 * (unlikely), then all we'll have done is given first dir
2916 		 * block a small amount of fragmentation.
2917 		 */
2918 		ocfs2_init_dir_trailer(dir, dirdata_bh, i);
2919 	}
2920 
2921 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
2922 	ocfs2_journal_dirty(handle, dirdata_bh);
2923 
2924 	if (ocfs2_supports_indexed_dirs(osb) && !dx_inline) {
2925 		/*
2926 		 * Dx dirs with an external cluster need to do this up
2927 		 * front. Inline dx root's get handled later, after
2928 		 * we've allocated our root block. We get passed back
2929 		 * a total number of items so that dr_num_entries can
2930 		 * be correctly set once the dx_root has been
2931 		 * allocated.
2932 		 */
2933 		ret = ocfs2_dx_dir_index_block(dir, handle, dx_leaves,
2934 					       num_dx_leaves, &num_dx_entries,
2935 					       dirdata_bh);
2936 		if (ret) {
2937 			mlog_errno(ret);
2938 			goto out_commit;
2939 		}
2940 	}
2941 
2942 	/*
2943 	 * Set extent, i_size, etc on the directory. After this, the
2944 	 * inode should contain the same exact dirents as before and
2945 	 * be fully accessible from system calls.
2946 	 *
2947 	 * We let the later dirent insert modify c/mtime - to the user
2948 	 * the data hasn't changed.
2949 	 */
2950 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
2951 				      OCFS2_JOURNAL_ACCESS_CREATE);
2952 	if (ret) {
2953 		mlog_errno(ret);
2954 		goto out_commit;
2955 	}
2956 
2957 	spin_lock(&oi->ip_lock);
2958 	oi->ip_dyn_features &= ~OCFS2_INLINE_DATA_FL;
2959 	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
2960 	spin_unlock(&oi->ip_lock);
2961 
2962 	ocfs2_dinode_new_extent_list(dir, di);
2963 
2964 	i_size_write(dir, sb->s_blocksize);
2965 	dir->i_mtime = dir->i_ctime = current_time(dir);
2966 
2967 	di->i_size = cpu_to_le64(sb->s_blocksize);
2968 	di->i_ctime = di->i_mtime = cpu_to_le64(dir->i_ctime.tv_sec);
2969 	di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(dir->i_ctime.tv_nsec);
2970 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
2971 
2972 	/*
2973 	 * This should never fail as our extent list is empty and all
2974 	 * related blocks have been journaled already.
2975 	 */
2976 	ret = ocfs2_insert_extent(handle, &et, 0, blkno, len,
2977 				  0, NULL);
2978 	if (ret) {
2979 		mlog_errno(ret);
2980 		goto out_commit;
2981 	}
2982 
2983 	/*
2984 	 * Set i_blocks after the extent insert for the most up to
2985 	 * date ip_clusters value.
2986 	 */
2987 	dir->i_blocks = ocfs2_inode_sector_count(dir);
2988 
2989 	ocfs2_journal_dirty(handle, di_bh);
2990 
2991 	if (ocfs2_supports_indexed_dirs(osb)) {
2992 		ret = ocfs2_dx_dir_attach_index(osb, handle, dir, di_bh,
2993 						dirdata_bh, meta_ac, dx_inline,
2994 						num_dx_entries, &dx_root_bh);
2995 		if (ret) {
2996 			mlog_errno(ret);
2997 			goto out_commit;
2998 		}
2999 
3000 		if (dx_inline) {
3001 			ocfs2_dx_dir_index_root_block(dir, dx_root_bh,
3002 						      dirdata_bh);
3003 		} else {
3004 			ocfs2_init_dx_root_extent_tree(&dx_et,
3005 						       INODE_CACHE(dir),
3006 						       dx_root_bh);
3007 			ret = ocfs2_insert_extent(handle, &dx_et, 0,
3008 						  dx_insert_blkno, 1, 0, NULL);
3009 			if (ret)
3010 				mlog_errno(ret);
3011 		}
3012 	}
3013 
3014 	/*
3015 	 * We asked for two clusters, but only got one in the 1st
3016 	 * pass. Claim the 2nd cluster as a separate extent.
3017 	 */
3018 	if (alloc > len) {
3019 		ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off,
3020 					   &len);
3021 		if (ret) {
3022 			mlog_errno(ret);
3023 			goto out_commit;
3024 		}
3025 		blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
3026 
3027 		ret = ocfs2_insert_extent(handle, &et, 1,
3028 					  blkno, len, 0, NULL);
3029 		if (ret) {
3030 			mlog_errno(ret);
3031 			goto out_commit;
3032 		}
3033 		bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
3034 	}
3035 
3036 	*first_block_bh = dirdata_bh;
3037 	dirdata_bh = NULL;
3038 	if (ocfs2_supports_indexed_dirs(osb)) {
3039 		unsigned int off;
3040 
3041 		if (!dx_inline) {
3042 			/*
3043 			 * We need to return the correct block within the
3044 			 * cluster which should hold our entry.
3045 			 */
3046 			off = ocfs2_dx_dir_hash_idx(osb,
3047 						    &lookup->dl_hinfo);
3048 			get_bh(dx_leaves[off]);
3049 			lookup->dl_dx_leaf_bh = dx_leaves[off];
3050 		}
3051 		lookup->dl_dx_root_bh = dx_root_bh;
3052 		dx_root_bh = NULL;
3053 	}
3054 
3055 out_commit:
3056 	if (ret < 0 && did_quota)
3057 		dquot_free_space_nodirty(dir, bytes_allocated);
3058 
3059 	ocfs2_commit_trans(osb, handle);
3060 
3061 out:
3062 	up_write(&oi->ip_alloc_sem);
3063 	if (data_ac)
3064 		ocfs2_free_alloc_context(data_ac);
3065 	if (meta_ac)
3066 		ocfs2_free_alloc_context(meta_ac);
3067 
3068 	if (dx_leaves) {
3069 		for (i = 0; i < num_dx_leaves; i++)
3070 			brelse(dx_leaves[i]);
3071 		kfree(dx_leaves);
3072 	}
3073 
3074 	brelse(dirdata_bh);
3075 	brelse(dx_root_bh);
3076 
3077 	return ret;
3078 }
3079 
3080 /* returns a bh of the 1st new block in the allocation. */
3081 static int ocfs2_do_extend_dir(struct super_block *sb,
3082 			       handle_t *handle,
3083 			       struct inode *dir,
3084 			       struct buffer_head *parent_fe_bh,
3085 			       struct ocfs2_alloc_context *data_ac,
3086 			       struct ocfs2_alloc_context *meta_ac,
3087 			       struct buffer_head **new_bh)
3088 {
3089 	int status;
3090 	int extend, did_quota = 0;
3091 	u64 p_blkno, v_blkno;
3092 
3093 	spin_lock(&OCFS2_I(dir)->ip_lock);
3094 	extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
3095 	spin_unlock(&OCFS2_I(dir)->ip_lock);
3096 
3097 	if (extend) {
3098 		u32 offset = OCFS2_I(dir)->ip_clusters;
3099 
3100 		status = dquot_alloc_space_nodirty(dir,
3101 					ocfs2_clusters_to_bytes(sb, 1));
3102 		if (status)
3103 			goto bail;
3104 		did_quota = 1;
3105 
3106 		status = ocfs2_add_inode_data(OCFS2_SB(sb), dir, &offset,
3107 					      1, 0, parent_fe_bh, handle,
3108 					      data_ac, meta_ac, NULL);
3109 		BUG_ON(status == -EAGAIN);
3110 		if (status < 0) {
3111 			mlog_errno(status);
3112 			goto bail;
3113 		}
3114 	}
3115 
3116 	v_blkno = ocfs2_blocks_for_bytes(sb, i_size_read(dir));
3117 	status = ocfs2_extent_map_get_blocks(dir, v_blkno, &p_blkno, NULL, NULL);
3118 	if (status < 0) {
3119 		mlog_errno(status);
3120 		goto bail;
3121 	}
3122 
3123 	*new_bh = sb_getblk(sb, p_blkno);
3124 	if (!*new_bh) {
3125 		status = -ENOMEM;
3126 		mlog_errno(status);
3127 		goto bail;
3128 	}
3129 	status = 0;
3130 bail:
3131 	if (did_quota && status < 0)
3132 		dquot_free_space_nodirty(dir, ocfs2_clusters_to_bytes(sb, 1));
3133 	return status;
3134 }
3135 
3136 /*
3137  * Assumes you already have a cluster lock on the directory.
3138  *
3139  * 'blocks_wanted' is only used if we have an inline directory which
3140  * is to be turned into an extent based one. The size of the dirent to
3141  * insert might be larger than the space gained by growing to just one
3142  * block, so we may have to grow the inode by two blocks in that case.
3143  *
3144  * If the directory is already indexed, dx_root_bh must be provided.
3145  */
3146 static int ocfs2_extend_dir(struct ocfs2_super *osb,
3147 			    struct inode *dir,
3148 			    struct buffer_head *parent_fe_bh,
3149 			    unsigned int blocks_wanted,
3150 			    struct ocfs2_dir_lookup_result *lookup,
3151 			    struct buffer_head **new_de_bh)
3152 {
3153 	int status = 0;
3154 	int credits, num_free_extents, drop_alloc_sem = 0;
3155 	loff_t dir_i_size;
3156 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
3157 	struct ocfs2_extent_list *el = &fe->id2.i_list;
3158 	struct ocfs2_alloc_context *data_ac = NULL;
3159 	struct ocfs2_alloc_context *meta_ac = NULL;
3160 	handle_t *handle = NULL;
3161 	struct buffer_head *new_bh = NULL;
3162 	struct ocfs2_dir_entry * de;
3163 	struct super_block *sb = osb->sb;
3164 	struct ocfs2_extent_tree et;
3165 	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
3166 
3167 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
3168 		/*
3169 		 * This would be a code error as an inline directory should
3170 		 * never have an index root.
3171 		 */
3172 		BUG_ON(dx_root_bh);
3173 
3174 		status = ocfs2_expand_inline_dir(dir, parent_fe_bh,
3175 						 blocks_wanted, lookup,
3176 						 &new_bh);
3177 		if (status) {
3178 			mlog_errno(status);
3179 			goto bail;
3180 		}
3181 
3182 		/* Expansion from inline to an indexed directory will
3183 		 * have given us this. */
3184 		dx_root_bh = lookup->dl_dx_root_bh;
3185 
3186 		if (blocks_wanted == 1) {
3187 			/*
3188 			 * If the new dirent will fit inside the space
3189 			 * created by pushing out to one block, then
3190 			 * we can complete the operation
3191 			 * here. Otherwise we have to expand i_size
3192 			 * and format the 2nd block below.
3193 			 */
3194 			BUG_ON(new_bh == NULL);
3195 			goto bail_bh;
3196 		}
3197 
3198 		/*
3199 		 * Get rid of 'new_bh' - we want to format the 2nd
3200 		 * data block and return that instead.
3201 		 */
3202 		brelse(new_bh);
3203 		new_bh = NULL;
3204 
3205 		down_write(&OCFS2_I(dir)->ip_alloc_sem);
3206 		drop_alloc_sem = 1;
3207 		dir_i_size = i_size_read(dir);
3208 		credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
3209 		goto do_extend;
3210 	}
3211 
3212 	down_write(&OCFS2_I(dir)->ip_alloc_sem);
3213 	drop_alloc_sem = 1;
3214 	dir_i_size = i_size_read(dir);
3215 	trace_ocfs2_extend_dir((unsigned long long)OCFS2_I(dir)->ip_blkno,
3216 			       dir_i_size);
3217 
3218 	/* dir->i_size is always block aligned. */
3219 	spin_lock(&OCFS2_I(dir)->ip_lock);
3220 	if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
3221 		spin_unlock(&OCFS2_I(dir)->ip_lock);
3222 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(dir),
3223 					      parent_fe_bh);
3224 		num_free_extents = ocfs2_num_free_extents(&et);
3225 		if (num_free_extents < 0) {
3226 			status = num_free_extents;
3227 			mlog_errno(status);
3228 			goto bail;
3229 		}
3230 
3231 		if (!num_free_extents) {
3232 			status = ocfs2_reserve_new_metadata(osb, el, &meta_ac);
3233 			if (status < 0) {
3234 				if (status != -ENOSPC)
3235 					mlog_errno(status);
3236 				goto bail;
3237 			}
3238 		}
3239 
3240 		status = ocfs2_reserve_clusters(osb, 1, &data_ac);
3241 		if (status < 0) {
3242 			if (status != -ENOSPC)
3243 				mlog_errno(status);
3244 			goto bail;
3245 		}
3246 
3247 		if (ocfs2_dir_resv_allowed(osb))
3248 			data_ac->ac_resv = &OCFS2_I(dir)->ip_la_data_resv;
3249 
3250 		credits = ocfs2_calc_extend_credits(sb, el);
3251 	} else {
3252 		spin_unlock(&OCFS2_I(dir)->ip_lock);
3253 		credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
3254 	}
3255 
3256 do_extend:
3257 	if (ocfs2_dir_indexed(dir))
3258 		credits++; /* For attaching the new dirent block to the
3259 			    * dx_root */
3260 
3261 	handle = ocfs2_start_trans(osb, credits);
3262 	if (IS_ERR(handle)) {
3263 		status = PTR_ERR(handle);
3264 		handle = NULL;
3265 		mlog_errno(status);
3266 		goto bail;
3267 	}
3268 
3269 	status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
3270 				     data_ac, meta_ac, &new_bh);
3271 	if (status < 0) {
3272 		mlog_errno(status);
3273 		goto bail;
3274 	}
3275 
3276 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), new_bh);
3277 
3278 	status = ocfs2_journal_access_db(handle, INODE_CACHE(dir), new_bh,
3279 					 OCFS2_JOURNAL_ACCESS_CREATE);
3280 	if (status < 0) {
3281 		mlog_errno(status);
3282 		goto bail;
3283 	}
3284 	memset(new_bh->b_data, 0, sb->s_blocksize);
3285 
3286 	de = (struct ocfs2_dir_entry *) new_bh->b_data;
3287 	de->inode = 0;
3288 	if (ocfs2_supports_dir_trailer(dir)) {
3289 		de->rec_len = cpu_to_le16(ocfs2_dir_trailer_blk_off(sb));
3290 
3291 		ocfs2_init_dir_trailer(dir, new_bh, le16_to_cpu(de->rec_len));
3292 
3293 		if (ocfs2_dir_indexed(dir)) {
3294 			status = ocfs2_dx_dir_link_trailer(dir, handle,
3295 							   dx_root_bh, new_bh);
3296 			if (status) {
3297 				mlog_errno(status);
3298 				goto bail;
3299 			}
3300 		}
3301 	} else {
3302 		de->rec_len = cpu_to_le16(sb->s_blocksize);
3303 	}
3304 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
3305 	ocfs2_journal_dirty(handle, new_bh);
3306 
3307 	dir_i_size += dir->i_sb->s_blocksize;
3308 	i_size_write(dir, dir_i_size);
3309 	dir->i_blocks = ocfs2_inode_sector_count(dir);
3310 	status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
3311 	if (status < 0) {
3312 		mlog_errno(status);
3313 		goto bail;
3314 	}
3315 
3316 bail_bh:
3317 	*new_de_bh = new_bh;
3318 	get_bh(*new_de_bh);
3319 bail:
3320 	if (handle)
3321 		ocfs2_commit_trans(osb, handle);
3322 	if (drop_alloc_sem)
3323 		up_write(&OCFS2_I(dir)->ip_alloc_sem);
3324 
3325 	if (data_ac)
3326 		ocfs2_free_alloc_context(data_ac);
3327 	if (meta_ac)
3328 		ocfs2_free_alloc_context(meta_ac);
3329 
3330 	brelse(new_bh);
3331 
3332 	return status;
3333 }
3334 
3335 static int ocfs2_find_dir_space_id(struct inode *dir, struct buffer_head *di_bh,
3336 				   const char *name, int namelen,
3337 				   struct buffer_head **ret_de_bh,
3338 				   unsigned int *blocks_wanted)
3339 {
3340 	int ret;
3341 	struct super_block *sb = dir->i_sb;
3342 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
3343 	struct ocfs2_dir_entry *de, *last_de = NULL;
3344 	char *de_buf, *limit;
3345 	unsigned long offset = 0;
3346 	unsigned int rec_len, new_rec_len, free_space = dir->i_sb->s_blocksize;
3347 
3348 	/*
3349 	 * This calculates how many free bytes we'd have in block zero, should
3350 	 * this function force expansion to an extent tree.
3351 	 */
3352 	if (ocfs2_new_dir_wants_trailer(dir))
3353 		free_space = ocfs2_dir_trailer_blk_off(sb) - i_size_read(dir);
3354 	else
3355 		free_space = dir->i_sb->s_blocksize - i_size_read(dir);
3356 
3357 	de_buf = di->id2.i_data.id_data;
3358 	limit = de_buf + i_size_read(dir);
3359 	rec_len = OCFS2_DIR_REC_LEN(namelen);
3360 
3361 	while (de_buf < limit) {
3362 		de = (struct ocfs2_dir_entry *)de_buf;
3363 
3364 		if (!ocfs2_check_dir_entry(dir, de, di_bh, offset)) {
3365 			ret = -ENOENT;
3366 			goto out;
3367 		}
3368 		if (ocfs2_match(namelen, name, de)) {
3369 			ret = -EEXIST;
3370 			goto out;
3371 		}
3372 		/*
3373 		 * No need to check for a trailing dirent record here as
3374 		 * they're not used for inline dirs.
3375 		 */
3376 
3377 		if (ocfs2_dirent_would_fit(de, rec_len)) {
3378 			/* Ok, we found a spot. Return this bh and let
3379 			 * the caller actually fill it in. */
3380 			*ret_de_bh = di_bh;
3381 			get_bh(*ret_de_bh);
3382 			ret = 0;
3383 			goto out;
3384 		}
3385 
3386 		last_de = de;
3387 		de_buf += le16_to_cpu(de->rec_len);
3388 		offset += le16_to_cpu(de->rec_len);
3389 	}
3390 
3391 	/*
3392 	 * We're going to require expansion of the directory - figure
3393 	 * out how many blocks we'll need so that a place for the
3394 	 * dirent can be found.
3395 	 */
3396 	*blocks_wanted = 1;
3397 	new_rec_len = le16_to_cpu(last_de->rec_len) + free_space;
3398 	if (new_rec_len < (rec_len + OCFS2_DIR_REC_LEN(last_de->name_len)))
3399 		*blocks_wanted = 2;
3400 
3401 	ret = -ENOSPC;
3402 out:
3403 	return ret;
3404 }
3405 
3406 static int ocfs2_find_dir_space_el(struct inode *dir, const char *name,
3407 				   int namelen, struct buffer_head **ret_de_bh)
3408 {
3409 	unsigned long offset;
3410 	struct buffer_head *bh = NULL;
3411 	unsigned short rec_len;
3412 	struct ocfs2_dir_entry *de;
3413 	struct super_block *sb = dir->i_sb;
3414 	int status;
3415 	int blocksize = dir->i_sb->s_blocksize;
3416 
3417 	status = ocfs2_read_dir_block(dir, 0, &bh, 0);
3418 	if (status)
3419 		goto bail;
3420 
3421 	rec_len = OCFS2_DIR_REC_LEN(namelen);
3422 	offset = 0;
3423 	de = (struct ocfs2_dir_entry *) bh->b_data;
3424 	while (1) {
3425 		if ((char *)de >= sb->s_blocksize + bh->b_data) {
3426 			brelse(bh);
3427 			bh = NULL;
3428 
3429 			if (i_size_read(dir) <= offset) {
3430 				/*
3431 				 * Caller will have to expand this
3432 				 * directory.
3433 				 */
3434 				status = -ENOSPC;
3435 				goto bail;
3436 			}
3437 			status = ocfs2_read_dir_block(dir,
3438 					     offset >> sb->s_blocksize_bits,
3439 					     &bh, 0);
3440 			if (status)
3441 				goto bail;
3442 
3443 			/* move to next block */
3444 			de = (struct ocfs2_dir_entry *) bh->b_data;
3445 		}
3446 		if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
3447 			status = -ENOENT;
3448 			goto bail;
3449 		}
3450 		if (ocfs2_match(namelen, name, de)) {
3451 			status = -EEXIST;
3452 			goto bail;
3453 		}
3454 
3455 		if (ocfs2_skip_dir_trailer(dir, de, offset % blocksize,
3456 					   blocksize))
3457 			goto next;
3458 
3459 		if (ocfs2_dirent_would_fit(de, rec_len)) {
3460 			/* Ok, we found a spot. Return this bh and let
3461 			 * the caller actually fill it in. */
3462 			*ret_de_bh = bh;
3463 			get_bh(*ret_de_bh);
3464 			status = 0;
3465 			goto bail;
3466 		}
3467 next:
3468 		offset += le16_to_cpu(de->rec_len);
3469 		de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
3470 	}
3471 
3472 bail:
3473 	brelse(bh);
3474 	if (status)
3475 		mlog_errno(status);
3476 
3477 	return status;
3478 }
3479 
3480 static int dx_leaf_sort_cmp(const void *a, const void *b)
3481 {
3482 	const struct ocfs2_dx_entry *entry1 = a;
3483 	const struct ocfs2_dx_entry *entry2 = b;
3484 	u32 major_hash1 = le32_to_cpu(entry1->dx_major_hash);
3485 	u32 major_hash2 = le32_to_cpu(entry2->dx_major_hash);
3486 	u32 minor_hash1 = le32_to_cpu(entry1->dx_minor_hash);
3487 	u32 minor_hash2 = le32_to_cpu(entry2->dx_minor_hash);
3488 
3489 	if (major_hash1 > major_hash2)
3490 		return 1;
3491 	if (major_hash1 < major_hash2)
3492 		return -1;
3493 
3494 	/*
3495 	 * It is not strictly necessary to sort by minor
3496 	 */
3497 	if (minor_hash1 > minor_hash2)
3498 		return 1;
3499 	if (minor_hash1 < minor_hash2)
3500 		return -1;
3501 	return 0;
3502 }
3503 
3504 static void dx_leaf_sort_swap(void *a, void *b, int size)
3505 {
3506 	struct ocfs2_dx_entry *entry1 = a;
3507 	struct ocfs2_dx_entry *entry2 = b;
3508 
3509 	BUG_ON(size != sizeof(*entry1));
3510 
3511 	swap(*entry1, *entry2);
3512 }
3513 
3514 static int ocfs2_dx_leaf_same_major(struct ocfs2_dx_leaf *dx_leaf)
3515 {
3516 	struct ocfs2_dx_entry_list *dl_list = &dx_leaf->dl_list;
3517 	int i, num = le16_to_cpu(dl_list->de_num_used);
3518 
3519 	for (i = 0; i < (num - 1); i++) {
3520 		if (le32_to_cpu(dl_list->de_entries[i].dx_major_hash) !=
3521 		    le32_to_cpu(dl_list->de_entries[i + 1].dx_major_hash))
3522 			return 0;
3523 	}
3524 
3525 	return 1;
3526 }
3527 
3528 /*
3529  * Find the optimal value to split this leaf on. This expects the leaf
3530  * entries to be in sorted order.
3531  *
3532  * leaf_cpos is the cpos of the leaf we're splitting. insert_hash is
3533  * the hash we want to insert.
3534  *
3535  * This function is only concerned with the major hash - that which
3536  * determines which cluster an item belongs to.
3537  */
3538 static int ocfs2_dx_dir_find_leaf_split(struct ocfs2_dx_leaf *dx_leaf,
3539 					u32 leaf_cpos, u32 insert_hash,
3540 					u32 *split_hash)
3541 {
3542 	struct ocfs2_dx_entry_list *dl_list = &dx_leaf->dl_list;
3543 	int i, num_used = le16_to_cpu(dl_list->de_num_used);
3544 	int allsame;
3545 
3546 	/*
3547 	 * There's a couple rare, but nasty corner cases we have to
3548 	 * check for here. All of them involve a leaf where all value
3549 	 * have the same hash, which is what we look for first.
3550 	 *
3551 	 * Most of the time, all of the above is false, and we simply
3552 	 * pick the median value for a split.
3553 	 */
3554 	allsame = ocfs2_dx_leaf_same_major(dx_leaf);
3555 	if (allsame) {
3556 		u32 val = le32_to_cpu(dl_list->de_entries[0].dx_major_hash);
3557 
3558 		if (val == insert_hash) {
3559 			/*
3560 			 * No matter where we would choose to split,
3561 			 * the new entry would want to occupy the same
3562 			 * block as these. Since there's no space left
3563 			 * in their existing block, we know there
3564 			 * won't be space after the split.
3565 			 */
3566 			return -ENOSPC;
3567 		}
3568 
3569 		if (val == leaf_cpos) {
3570 			/*
3571 			 * Because val is the same as leaf_cpos (which
3572 			 * is the smallest value this leaf can have),
3573 			 * yet is not equal to insert_hash, then we
3574 			 * know that insert_hash *must* be larger than
3575 			 * val (and leaf_cpos). At least cpos+1 in value.
3576 			 *
3577 			 * We also know then, that there cannot be an
3578 			 * adjacent extent (otherwise we'd be looking
3579 			 * at it). Choosing this value gives us a
3580 			 * chance to get some contiguousness.
3581 			 */
3582 			*split_hash = leaf_cpos + 1;
3583 			return 0;
3584 		}
3585 
3586 		if (val > insert_hash) {
3587 			/*
3588 			 * val can not be the same as insert hash, and
3589 			 * also must be larger than leaf_cpos. Also,
3590 			 * we know that there can't be a leaf between
3591 			 * cpos and val, otherwise the entries with
3592 			 * hash 'val' would be there.
3593 			 */
3594 			*split_hash = val;
3595 			return 0;
3596 		}
3597 
3598 		*split_hash = insert_hash;
3599 		return 0;
3600 	}
3601 
3602 	/*
3603 	 * Since the records are sorted and the checks above
3604 	 * guaranteed that not all records in this block are the same,
3605 	 * we simple travel forward, from the median, and pick the 1st
3606 	 * record whose value is larger than leaf_cpos.
3607 	 */
3608 	for (i = (num_used / 2); i < num_used; i++)
3609 		if (le32_to_cpu(dl_list->de_entries[i].dx_major_hash) >
3610 		    leaf_cpos)
3611 			break;
3612 
3613 	BUG_ON(i == num_used); /* Should be impossible */
3614 	*split_hash = le32_to_cpu(dl_list->de_entries[i].dx_major_hash);
3615 	return 0;
3616 }
3617 
3618 /*
3619  * Transfer all entries in orig_dx_leaves whose major hash is equal to or
3620  * larger than split_hash into new_dx_leaves. We use a temporary
3621  * buffer (tmp_dx_leaf) to make the changes to the original leaf blocks.
3622  *
3623  * Since the block offset inside a leaf (cluster) is a constant mask
3624  * of minor_hash, we can optimize - an item at block offset X within
3625  * the original cluster, will be at offset X within the new cluster.
3626  */
3627 static void ocfs2_dx_dir_transfer_leaf(struct inode *dir, u32 split_hash,
3628 				       handle_t *handle,
3629 				       struct ocfs2_dx_leaf *tmp_dx_leaf,
3630 				       struct buffer_head **orig_dx_leaves,
3631 				       struct buffer_head **new_dx_leaves,
3632 				       int num_dx_leaves)
3633 {
3634 	int i, j, num_used;
3635 	u32 major_hash;
3636 	struct ocfs2_dx_leaf *orig_dx_leaf, *new_dx_leaf;
3637 	struct ocfs2_dx_entry_list *orig_list, *tmp_list;
3638 	struct ocfs2_dx_entry *dx_entry;
3639 
3640 	tmp_list = &tmp_dx_leaf->dl_list;
3641 
3642 	for (i = 0; i < num_dx_leaves; i++) {
3643 		orig_dx_leaf = (struct ocfs2_dx_leaf *) orig_dx_leaves[i]->b_data;
3644 		orig_list = &orig_dx_leaf->dl_list;
3645 		new_dx_leaf = (struct ocfs2_dx_leaf *) new_dx_leaves[i]->b_data;
3646 
3647 		num_used = le16_to_cpu(orig_list->de_num_used);
3648 
3649 		memcpy(tmp_dx_leaf, orig_dx_leaf, dir->i_sb->s_blocksize);
3650 		tmp_list->de_num_used = cpu_to_le16(0);
3651 		memset(&tmp_list->de_entries, 0, sizeof(*dx_entry)*num_used);
3652 
3653 		for (j = 0; j < num_used; j++) {
3654 			dx_entry = &orig_list->de_entries[j];
3655 			major_hash = le32_to_cpu(dx_entry->dx_major_hash);
3656 			if (major_hash >= split_hash)
3657 				ocfs2_dx_dir_leaf_insert_tail(new_dx_leaf,
3658 							      dx_entry);
3659 			else
3660 				ocfs2_dx_dir_leaf_insert_tail(tmp_dx_leaf,
3661 							      dx_entry);
3662 		}
3663 		memcpy(orig_dx_leaf, tmp_dx_leaf, dir->i_sb->s_blocksize);
3664 
3665 		ocfs2_journal_dirty(handle, orig_dx_leaves[i]);
3666 		ocfs2_journal_dirty(handle, new_dx_leaves[i]);
3667 	}
3668 }
3669 
3670 static int ocfs2_dx_dir_rebalance_credits(struct ocfs2_super *osb,
3671 					  struct ocfs2_dx_root_block *dx_root)
3672 {
3673 	int credits = ocfs2_clusters_to_blocks(osb->sb, 3);
3674 
3675 	credits += ocfs2_calc_extend_credits(osb->sb, &dx_root->dr_list);
3676 	credits += ocfs2_quota_trans_credits(osb->sb);
3677 	return credits;
3678 }
3679 
3680 /*
3681  * Find the median value in dx_leaf_bh and allocate a new leaf to move
3682  * half our entries into.
3683  */
3684 static int ocfs2_dx_dir_rebalance(struct ocfs2_super *osb, struct inode *dir,
3685 				  struct buffer_head *dx_root_bh,
3686 				  struct buffer_head *dx_leaf_bh,
3687 				  struct ocfs2_dx_hinfo *hinfo, u32 leaf_cpos,
3688 				  u64 leaf_blkno)
3689 {
3690 	struct ocfs2_dx_leaf *dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
3691 	int credits, ret, i, num_used, did_quota = 0;
3692 	u32 cpos, split_hash, insert_hash = hinfo->major_hash;
3693 	u64 orig_leaves_start;
3694 	int num_dx_leaves;
3695 	struct buffer_head **orig_dx_leaves = NULL;
3696 	struct buffer_head **new_dx_leaves = NULL;
3697 	struct ocfs2_alloc_context *data_ac = NULL, *meta_ac = NULL;
3698 	struct ocfs2_extent_tree et;
3699 	handle_t *handle = NULL;
3700 	struct ocfs2_dx_root_block *dx_root;
3701 	struct ocfs2_dx_leaf *tmp_dx_leaf = NULL;
3702 
3703 	trace_ocfs2_dx_dir_rebalance((unsigned long long)OCFS2_I(dir)->ip_blkno,
3704 				     (unsigned long long)leaf_blkno,
3705 				     insert_hash);
3706 
3707 	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
3708 
3709 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
3710 	/*
3711 	 * XXX: This is a rather large limit. We should use a more
3712 	 * realistic value.
3713 	 */
3714 	if (le32_to_cpu(dx_root->dr_clusters) == UINT_MAX)
3715 		return -ENOSPC;
3716 
3717 	num_used = le16_to_cpu(dx_leaf->dl_list.de_num_used);
3718 	if (num_used < le16_to_cpu(dx_leaf->dl_list.de_count)) {
3719 		mlog(ML_ERROR, "DX Dir: %llu, Asked to rebalance empty leaf: "
3720 		     "%llu, %d\n", (unsigned long long)OCFS2_I(dir)->ip_blkno,
3721 		     (unsigned long long)leaf_blkno, num_used);
3722 		ret = -EIO;
3723 		goto out;
3724 	}
3725 
3726 	orig_dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, &num_dx_leaves);
3727 	if (!orig_dx_leaves) {
3728 		ret = -ENOMEM;
3729 		mlog_errno(ret);
3730 		goto out;
3731 	}
3732 
3733 	new_dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, NULL);
3734 	if (!new_dx_leaves) {
3735 		ret = -ENOMEM;
3736 		mlog_errno(ret);
3737 		goto out;
3738 	}
3739 
3740 	ret = ocfs2_lock_allocators(dir, &et, 1, 0, &data_ac, &meta_ac);
3741 	if (ret) {
3742 		if (ret != -ENOSPC)
3743 			mlog_errno(ret);
3744 		goto out;
3745 	}
3746 
3747 	credits = ocfs2_dx_dir_rebalance_credits(osb, dx_root);
3748 	handle = ocfs2_start_trans(osb, credits);
3749 	if (IS_ERR(handle)) {
3750 		ret = PTR_ERR(handle);
3751 		handle = NULL;
3752 		mlog_errno(ret);
3753 		goto out;
3754 	}
3755 
3756 	ret = dquot_alloc_space_nodirty(dir,
3757 				       ocfs2_clusters_to_bytes(dir->i_sb, 1));
3758 	if (ret)
3759 		goto out_commit;
3760 	did_quota = 1;
3761 
3762 	ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), dx_leaf_bh,
3763 				      OCFS2_JOURNAL_ACCESS_WRITE);
3764 	if (ret) {
3765 		mlog_errno(ret);
3766 		goto out_commit;
3767 	}
3768 
3769 	/*
3770 	 * This block is changing anyway, so we can sort it in place.
3771 	 */
3772 	sort(dx_leaf->dl_list.de_entries, num_used,
3773 	     sizeof(struct ocfs2_dx_entry), dx_leaf_sort_cmp,
3774 	     dx_leaf_sort_swap);
3775 
3776 	ocfs2_journal_dirty(handle, dx_leaf_bh);
3777 
3778 	ret = ocfs2_dx_dir_find_leaf_split(dx_leaf, leaf_cpos, insert_hash,
3779 					   &split_hash);
3780 	if (ret) {
3781 		mlog_errno(ret);
3782 		goto  out_commit;
3783 	}
3784 
3785 	trace_ocfs2_dx_dir_rebalance_split(leaf_cpos, split_hash, insert_hash);
3786 
3787 	/*
3788 	 * We have to carefully order operations here. There are items
3789 	 * which want to be in the new cluster before insert, but in
3790 	 * order to put those items in the new cluster, we alter the
3791 	 * old cluster. A failure to insert gets nasty.
3792 	 *
3793 	 * So, start by reserving writes to the old
3794 	 * cluster. ocfs2_dx_dir_new_cluster will reserve writes on
3795 	 * the new cluster for us, before inserting it. The insert
3796 	 * won't happen if there's an error before that. Once the
3797 	 * insert is done then, we can transfer from one leaf into the
3798 	 * other without fear of hitting any error.
3799 	 */
3800 
3801 	/*
3802 	 * The leaf transfer wants some scratch space so that we don't
3803 	 * wind up doing a bunch of expensive memmove().
3804 	 */
3805 	tmp_dx_leaf = kmalloc(osb->sb->s_blocksize, GFP_NOFS);
3806 	if (!tmp_dx_leaf) {
3807 		ret = -ENOMEM;
3808 		mlog_errno(ret);
3809 		goto out_commit;
3810 	}
3811 
3812 	orig_leaves_start = ocfs2_block_to_cluster_start(dir->i_sb, leaf_blkno);
3813 	ret = ocfs2_read_dx_leaves(dir, orig_leaves_start, num_dx_leaves,
3814 				   orig_dx_leaves);
3815 	if (ret) {
3816 		mlog_errno(ret);
3817 		goto out_commit;
3818 	}
3819 
3820 	cpos = split_hash;
3821 	ret = ocfs2_dx_dir_new_cluster(dir, &et, cpos, handle,
3822 				       data_ac, meta_ac, new_dx_leaves,
3823 				       num_dx_leaves);
3824 	if (ret) {
3825 		mlog_errno(ret);
3826 		goto out_commit;
3827 	}
3828 
3829 	for (i = 0; i < num_dx_leaves; i++) {
3830 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
3831 					      orig_dx_leaves[i],
3832 					      OCFS2_JOURNAL_ACCESS_WRITE);
3833 		if (ret) {
3834 			mlog_errno(ret);
3835 			goto out_commit;
3836 		}
3837 
3838 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
3839 					      new_dx_leaves[i],
3840 					      OCFS2_JOURNAL_ACCESS_WRITE);
3841 		if (ret) {
3842 			mlog_errno(ret);
3843 			goto out_commit;
3844 		}
3845 	}
3846 
3847 	ocfs2_dx_dir_transfer_leaf(dir, split_hash, handle, tmp_dx_leaf,
3848 				   orig_dx_leaves, new_dx_leaves, num_dx_leaves);
3849 
3850 out_commit:
3851 	if (ret < 0 && did_quota)
3852 		dquot_free_space_nodirty(dir,
3853 				ocfs2_clusters_to_bytes(dir->i_sb, 1));
3854 
3855 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
3856 	ocfs2_commit_trans(osb, handle);
3857 
3858 out:
3859 	if (orig_dx_leaves || new_dx_leaves) {
3860 		for (i = 0; i < num_dx_leaves; i++) {
3861 			if (orig_dx_leaves)
3862 				brelse(orig_dx_leaves[i]);
3863 			if (new_dx_leaves)
3864 				brelse(new_dx_leaves[i]);
3865 		}
3866 		kfree(orig_dx_leaves);
3867 		kfree(new_dx_leaves);
3868 	}
3869 
3870 	if (meta_ac)
3871 		ocfs2_free_alloc_context(meta_ac);
3872 	if (data_ac)
3873 		ocfs2_free_alloc_context(data_ac);
3874 
3875 	kfree(tmp_dx_leaf);
3876 	return ret;
3877 }
3878 
3879 static int ocfs2_find_dir_space_dx(struct ocfs2_super *osb, struct inode *dir,
3880 				   struct buffer_head *di_bh,
3881 				   struct buffer_head *dx_root_bh,
3882 				   const char *name, int namelen,
3883 				   struct ocfs2_dir_lookup_result *lookup)
3884 {
3885 	int ret, rebalanced = 0;
3886 	struct ocfs2_dx_root_block *dx_root;
3887 	struct buffer_head *dx_leaf_bh = NULL;
3888 	struct ocfs2_dx_leaf *dx_leaf;
3889 	u64 blkno;
3890 	u32 leaf_cpos;
3891 
3892 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
3893 
3894 restart_search:
3895 	ret = ocfs2_dx_dir_lookup(dir, &dx_root->dr_list, &lookup->dl_hinfo,
3896 				  &leaf_cpos, &blkno);
3897 	if (ret) {
3898 		mlog_errno(ret);
3899 		goto out;
3900 	}
3901 
3902 	ret = ocfs2_read_dx_leaf(dir, blkno, &dx_leaf_bh);
3903 	if (ret) {
3904 		mlog_errno(ret);
3905 		goto out;
3906 	}
3907 
3908 	dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
3909 
3910 	if (le16_to_cpu(dx_leaf->dl_list.de_num_used) >=
3911 	    le16_to_cpu(dx_leaf->dl_list.de_count)) {
3912 		if (rebalanced) {
3913 			/*
3914 			 * Rebalancing should have provided us with
3915 			 * space in an appropriate leaf.
3916 			 *
3917 			 * XXX: Is this an abnormal condition then?
3918 			 * Should we print a message here?
3919 			 */
3920 			ret = -ENOSPC;
3921 			goto out;
3922 		}
3923 
3924 		ret = ocfs2_dx_dir_rebalance(osb, dir, dx_root_bh, dx_leaf_bh,
3925 					     &lookup->dl_hinfo, leaf_cpos,
3926 					     blkno);
3927 		if (ret) {
3928 			if (ret != -ENOSPC)
3929 				mlog_errno(ret);
3930 			goto out;
3931 		}
3932 
3933 		/*
3934 		 * Restart the lookup. The rebalance might have
3935 		 * changed which block our item fits into. Mark our
3936 		 * progress, so we only execute this once.
3937 		 */
3938 		brelse(dx_leaf_bh);
3939 		dx_leaf_bh = NULL;
3940 		rebalanced = 1;
3941 		goto restart_search;
3942 	}
3943 
3944 	lookup->dl_dx_leaf_bh = dx_leaf_bh;
3945 	dx_leaf_bh = NULL;
3946 
3947 out:
3948 	brelse(dx_leaf_bh);
3949 	return ret;
3950 }
3951 
3952 static int ocfs2_search_dx_free_list(struct inode *dir,
3953 				     struct buffer_head *dx_root_bh,
3954 				     int namelen,
3955 				     struct ocfs2_dir_lookup_result *lookup)
3956 {
3957 	int ret = -ENOSPC;
3958 	struct buffer_head *leaf_bh = NULL, *prev_leaf_bh = NULL;
3959 	struct ocfs2_dir_block_trailer *db;
3960 	u64 next_block;
3961 	int rec_len = OCFS2_DIR_REC_LEN(namelen);
3962 	struct ocfs2_dx_root_block *dx_root;
3963 
3964 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
3965 	next_block = le64_to_cpu(dx_root->dr_free_blk);
3966 
3967 	while (next_block) {
3968 		brelse(prev_leaf_bh);
3969 		prev_leaf_bh = leaf_bh;
3970 		leaf_bh = NULL;
3971 
3972 		ret = ocfs2_read_dir_block_direct(dir, next_block, &leaf_bh);
3973 		if (ret) {
3974 			mlog_errno(ret);
3975 			goto out;
3976 		}
3977 
3978 		db = ocfs2_trailer_from_bh(leaf_bh, dir->i_sb);
3979 		if (rec_len <= le16_to_cpu(db->db_free_rec_len)) {
3980 			lookup->dl_leaf_bh = leaf_bh;
3981 			lookup->dl_prev_leaf_bh = prev_leaf_bh;
3982 			leaf_bh = NULL;
3983 			prev_leaf_bh = NULL;
3984 			break;
3985 		}
3986 
3987 		next_block = le64_to_cpu(db->db_free_next);
3988 	}
3989 
3990 	if (!next_block)
3991 		ret = -ENOSPC;
3992 
3993 out:
3994 
3995 	brelse(leaf_bh);
3996 	brelse(prev_leaf_bh);
3997 	return ret;
3998 }
3999 
4000 static int ocfs2_expand_inline_dx_root(struct inode *dir,
4001 				       struct buffer_head *dx_root_bh)
4002 {
4003 	int ret, num_dx_leaves, i, j, did_quota = 0;
4004 	struct buffer_head **dx_leaves = NULL;
4005 	struct ocfs2_extent_tree et;
4006 	u64 insert_blkno;
4007 	struct ocfs2_alloc_context *data_ac = NULL;
4008 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4009 	handle_t *handle = NULL;
4010 	struct ocfs2_dx_root_block *dx_root;
4011 	struct ocfs2_dx_entry_list *entry_list;
4012 	struct ocfs2_dx_entry *dx_entry;
4013 	struct ocfs2_dx_leaf *target_leaf;
4014 
4015 	ret = ocfs2_reserve_clusters(osb, 1, &data_ac);
4016 	if (ret) {
4017 		mlog_errno(ret);
4018 		goto out;
4019 	}
4020 
4021 	dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, &num_dx_leaves);
4022 	if (!dx_leaves) {
4023 		ret = -ENOMEM;
4024 		mlog_errno(ret);
4025 		goto out;
4026 	}
4027 
4028 	handle = ocfs2_start_trans(osb, ocfs2_calc_dxi_expand_credits(osb->sb));
4029 	if (IS_ERR(handle)) {
4030 		ret = PTR_ERR(handle);
4031 		mlog_errno(ret);
4032 		goto out;
4033 	}
4034 
4035 	ret = dquot_alloc_space_nodirty(dir,
4036 				       ocfs2_clusters_to_bytes(osb->sb, 1));
4037 	if (ret)
4038 		goto out_commit;
4039 	did_quota = 1;
4040 
4041 	/*
4042 	 * We do this up front, before the allocation, so that a
4043 	 * failure to add the dx_root_bh to the journal won't result
4044 	 * us losing clusters.
4045 	 */
4046 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
4047 				      OCFS2_JOURNAL_ACCESS_WRITE);
4048 	if (ret) {
4049 		mlog_errno(ret);
4050 		goto out_commit;
4051 	}
4052 
4053 	ret = __ocfs2_dx_dir_new_cluster(dir, 0, handle, data_ac, dx_leaves,
4054 					 num_dx_leaves, &insert_blkno);
4055 	if (ret) {
4056 		mlog_errno(ret);
4057 		goto out_commit;
4058 	}
4059 
4060 	/*
4061 	 * Transfer the entries from our dx_root into the appropriate
4062 	 * block
4063 	 */
4064 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
4065 	entry_list = &dx_root->dr_entries;
4066 
4067 	for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) {
4068 		dx_entry = &entry_list->de_entries[i];
4069 
4070 		j = __ocfs2_dx_dir_hash_idx(osb,
4071 					    le32_to_cpu(dx_entry->dx_minor_hash));
4072 		target_leaf = (struct ocfs2_dx_leaf *)dx_leaves[j]->b_data;
4073 
4074 		ocfs2_dx_dir_leaf_insert_tail(target_leaf, dx_entry);
4075 
4076 		/* Each leaf has been passed to the journal already
4077 		 * via __ocfs2_dx_dir_new_cluster() */
4078 	}
4079 
4080 	dx_root->dr_flags &= ~OCFS2_DX_FLAG_INLINE;
4081 	memset(&dx_root->dr_list, 0, osb->sb->s_blocksize -
4082 	       offsetof(struct ocfs2_dx_root_block, dr_list));
4083 	dx_root->dr_list.l_count =
4084 		cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
4085 
4086 	/* This should never fail considering we start with an empty
4087 	 * dx_root. */
4088 	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
4089 	ret = ocfs2_insert_extent(handle, &et, 0, insert_blkno, 1, 0, NULL);
4090 	if (ret)
4091 		mlog_errno(ret);
4092 	did_quota = 0;
4093 
4094 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
4095 	ocfs2_journal_dirty(handle, dx_root_bh);
4096 
4097 out_commit:
4098 	if (ret < 0 && did_quota)
4099 		dquot_free_space_nodirty(dir,
4100 					  ocfs2_clusters_to_bytes(dir->i_sb, 1));
4101 
4102 	ocfs2_commit_trans(osb, handle);
4103 
4104 out:
4105 	if (data_ac)
4106 		ocfs2_free_alloc_context(data_ac);
4107 
4108 	if (dx_leaves) {
4109 		for (i = 0; i < num_dx_leaves; i++)
4110 			brelse(dx_leaves[i]);
4111 		kfree(dx_leaves);
4112 	}
4113 	return ret;
4114 }
4115 
4116 static int ocfs2_inline_dx_has_space(struct buffer_head *dx_root_bh)
4117 {
4118 	struct ocfs2_dx_root_block *dx_root;
4119 	struct ocfs2_dx_entry_list *entry_list;
4120 
4121 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
4122 	entry_list = &dx_root->dr_entries;
4123 
4124 	if (le16_to_cpu(entry_list->de_num_used) >=
4125 	    le16_to_cpu(entry_list->de_count))
4126 		return -ENOSPC;
4127 
4128 	return 0;
4129 }
4130 
4131 static int ocfs2_prepare_dx_dir_for_insert(struct inode *dir,
4132 					   struct buffer_head *di_bh,
4133 					   const char *name,
4134 					   int namelen,
4135 					   struct ocfs2_dir_lookup_result *lookup)
4136 {
4137 	int ret, free_dx_root = 1;
4138 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4139 	struct buffer_head *dx_root_bh = NULL;
4140 	struct buffer_head *leaf_bh = NULL;
4141 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
4142 	struct ocfs2_dx_root_block *dx_root;
4143 
4144 	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
4145 	if (ret) {
4146 		mlog_errno(ret);
4147 		goto out;
4148 	}
4149 
4150 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
4151 	if (le32_to_cpu(dx_root->dr_num_entries) == OCFS2_DX_ENTRIES_MAX) {
4152 		ret = -ENOSPC;
4153 		mlog_errno(ret);
4154 		goto out;
4155 	}
4156 
4157 	if (ocfs2_dx_root_inline(dx_root)) {
4158 		ret = ocfs2_inline_dx_has_space(dx_root_bh);
4159 
4160 		if (ret == 0)
4161 			goto search_el;
4162 
4163 		/*
4164 		 * We ran out of room in the root block. Expand it to
4165 		 * an extent, then allow ocfs2_find_dir_space_dx to do
4166 		 * the rest.
4167 		 */
4168 		ret = ocfs2_expand_inline_dx_root(dir, dx_root_bh);
4169 		if (ret) {
4170 			mlog_errno(ret);
4171 			goto out;
4172 		}
4173 	}
4174 
4175 	/*
4176 	 * Insert preparation for an indexed directory is split into two
4177 	 * steps. The call to find_dir_space_dx reserves room in the index for
4178 	 * an additional item. If we run out of space there, it's a real error
4179 	 * we can't continue on.
4180 	 */
4181 	ret = ocfs2_find_dir_space_dx(osb, dir, di_bh, dx_root_bh, name,
4182 				      namelen, lookup);
4183 	if (ret) {
4184 		mlog_errno(ret);
4185 		goto out;
4186 	}
4187 
4188 search_el:
4189 	/*
4190 	 * Next, we need to find space in the unindexed tree. This call
4191 	 * searches using the free space linked list. If the unindexed tree
4192 	 * lacks sufficient space, we'll expand it below. The expansion code
4193 	 * is smart enough to add any new blocks to the free space list.
4194 	 */
4195 	ret = ocfs2_search_dx_free_list(dir, dx_root_bh, namelen, lookup);
4196 	if (ret && ret != -ENOSPC) {
4197 		mlog_errno(ret);
4198 		goto out;
4199 	}
4200 
4201 	/* Do this up here - ocfs2_extend_dir might need the dx_root */
4202 	lookup->dl_dx_root_bh = dx_root_bh;
4203 	free_dx_root = 0;
4204 
4205 	if (ret == -ENOSPC) {
4206 		ret = ocfs2_extend_dir(osb, dir, di_bh, 1, lookup, &leaf_bh);
4207 
4208 		if (ret) {
4209 			mlog_errno(ret);
4210 			goto out;
4211 		}
4212 
4213 		/*
4214 		 * We make the assumption here that new leaf blocks are added
4215 		 * to the front of our free list.
4216 		 */
4217 		lookup->dl_prev_leaf_bh = NULL;
4218 		lookup->dl_leaf_bh = leaf_bh;
4219 	}
4220 
4221 out:
4222 	if (free_dx_root)
4223 		brelse(dx_root_bh);
4224 	return ret;
4225 }
4226 
4227 /*
4228  * Get a directory ready for insert. Any directory allocation required
4229  * happens here. Success returns zero, and enough context in the dir
4230  * lookup result that ocfs2_add_entry() will be able complete the task
4231  * with minimal performance impact.
4232  */
4233 int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
4234 				 struct inode *dir,
4235 				 struct buffer_head *parent_fe_bh,
4236 				 const char *name,
4237 				 int namelen,
4238 				 struct ocfs2_dir_lookup_result *lookup)
4239 {
4240 	int ret;
4241 	unsigned int blocks_wanted = 1;
4242 	struct buffer_head *bh = NULL;
4243 
4244 	trace_ocfs2_prepare_dir_for_insert(
4245 		(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen);
4246 
4247 	if (!namelen) {
4248 		ret = -EINVAL;
4249 		mlog_errno(ret);
4250 		goto out;
4251 	}
4252 
4253 	/*
4254 	 * Do this up front to reduce confusion.
4255 	 *
4256 	 * The directory might start inline, then be turned into an
4257 	 * indexed one, in which case we'd need to hash deep inside
4258 	 * ocfs2_find_dir_space_id(). Since
4259 	 * ocfs2_prepare_dx_dir_for_insert() also needs this hash
4260 	 * done, there seems no point in spreading out the calls. We
4261 	 * can optimize away the case where the file system doesn't
4262 	 * support indexing.
4263 	 */
4264 	if (ocfs2_supports_indexed_dirs(osb))
4265 		ocfs2_dx_dir_name_hash(dir, name, namelen, &lookup->dl_hinfo);
4266 
4267 	if (ocfs2_dir_indexed(dir)) {
4268 		ret = ocfs2_prepare_dx_dir_for_insert(dir, parent_fe_bh,
4269 						      name, namelen, lookup);
4270 		if (ret)
4271 			mlog_errno(ret);
4272 		goto out;
4273 	}
4274 
4275 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
4276 		ret = ocfs2_find_dir_space_id(dir, parent_fe_bh, name,
4277 					      namelen, &bh, &blocks_wanted);
4278 	} else
4279 		ret = ocfs2_find_dir_space_el(dir, name, namelen, &bh);
4280 
4281 	if (ret && ret != -ENOSPC) {
4282 		mlog_errno(ret);
4283 		goto out;
4284 	}
4285 
4286 	if (ret == -ENOSPC) {
4287 		/*
4288 		 * We have to expand the directory to add this name.
4289 		 */
4290 		BUG_ON(bh);
4291 
4292 		ret = ocfs2_extend_dir(osb, dir, parent_fe_bh, blocks_wanted,
4293 				       lookup, &bh);
4294 		if (ret) {
4295 			if (ret != -ENOSPC)
4296 				mlog_errno(ret);
4297 			goto out;
4298 		}
4299 
4300 		BUG_ON(!bh);
4301 	}
4302 
4303 	lookup->dl_leaf_bh = bh;
4304 	bh = NULL;
4305 out:
4306 	brelse(bh);
4307 	return ret;
4308 }
4309 
4310 static int ocfs2_dx_dir_remove_index(struct inode *dir,
4311 				     struct buffer_head *di_bh,
4312 				     struct buffer_head *dx_root_bh)
4313 {
4314 	int ret;
4315 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4316 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
4317 	struct ocfs2_dx_root_block *dx_root;
4318 	struct inode *dx_alloc_inode = NULL;
4319 	struct buffer_head *dx_alloc_bh = NULL;
4320 	handle_t *handle;
4321 	u64 blk;
4322 	u16 bit;
4323 	u64 bg_blkno;
4324 
4325 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
4326 
4327 	dx_alloc_inode = ocfs2_get_system_file_inode(osb,
4328 					EXTENT_ALLOC_SYSTEM_INODE,
4329 					le16_to_cpu(dx_root->dr_suballoc_slot));
4330 	if (!dx_alloc_inode) {
4331 		ret = -ENOMEM;
4332 		mlog_errno(ret);
4333 		goto out;
4334 	}
4335 	inode_lock(dx_alloc_inode);
4336 
4337 	ret = ocfs2_inode_lock(dx_alloc_inode, &dx_alloc_bh, 1);
4338 	if (ret) {
4339 		mlog_errno(ret);
4340 		goto out_mutex;
4341 	}
4342 
4343 	handle = ocfs2_start_trans(osb, OCFS2_DX_ROOT_REMOVE_CREDITS);
4344 	if (IS_ERR(handle)) {
4345 		ret = PTR_ERR(handle);
4346 		mlog_errno(ret);
4347 		goto out_unlock;
4348 	}
4349 
4350 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
4351 				      OCFS2_JOURNAL_ACCESS_WRITE);
4352 	if (ret) {
4353 		mlog_errno(ret);
4354 		goto out_commit;
4355 	}
4356 
4357 	spin_lock(&OCFS2_I(dir)->ip_lock);
4358 	OCFS2_I(dir)->ip_dyn_features &= ~OCFS2_INDEXED_DIR_FL;
4359 	di->i_dyn_features = cpu_to_le16(OCFS2_I(dir)->ip_dyn_features);
4360 	spin_unlock(&OCFS2_I(dir)->ip_lock);
4361 	di->i_dx_root = cpu_to_le64(0ULL);
4362 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
4363 
4364 	ocfs2_journal_dirty(handle, di_bh);
4365 
4366 	blk = le64_to_cpu(dx_root->dr_blkno);
4367 	bit = le16_to_cpu(dx_root->dr_suballoc_bit);
4368 	if (dx_root->dr_suballoc_loc)
4369 		bg_blkno = le64_to_cpu(dx_root->dr_suballoc_loc);
4370 	else
4371 		bg_blkno = ocfs2_which_suballoc_group(blk, bit);
4372 	ret = ocfs2_free_suballoc_bits(handle, dx_alloc_inode, dx_alloc_bh,
4373 				       bit, bg_blkno, 1);
4374 	if (ret)
4375 		mlog_errno(ret);
4376 
4377 out_commit:
4378 	ocfs2_commit_trans(osb, handle);
4379 
4380 out_unlock:
4381 	ocfs2_inode_unlock(dx_alloc_inode, 1);
4382 
4383 out_mutex:
4384 	inode_unlock(dx_alloc_inode);
4385 	brelse(dx_alloc_bh);
4386 out:
4387 	iput(dx_alloc_inode);
4388 	return ret;
4389 }
4390 
4391 int ocfs2_dx_dir_truncate(struct inode *dir, struct buffer_head *di_bh)
4392 {
4393 	int ret;
4394 	unsigned int clen;
4395 	u32 major_hash = UINT_MAX, p_cpos, cpos;
4396 	u64 blkno;
4397 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4398 	struct buffer_head *dx_root_bh = NULL;
4399 	struct ocfs2_dx_root_block *dx_root;
4400 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
4401 	struct ocfs2_cached_dealloc_ctxt dealloc;
4402 	struct ocfs2_extent_tree et;
4403 
4404 	ocfs2_init_dealloc_ctxt(&dealloc);
4405 
4406 	if (!ocfs2_dir_indexed(dir))
4407 		return 0;
4408 
4409 	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
4410 	if (ret) {
4411 		mlog_errno(ret);
4412 		goto out;
4413 	}
4414 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
4415 
4416 	if (ocfs2_dx_root_inline(dx_root))
4417 		goto remove_index;
4418 
4419 	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
4420 
4421 	/* XXX: What if dr_clusters is too large? */
4422 	while (le32_to_cpu(dx_root->dr_clusters)) {
4423 		ret = ocfs2_dx_dir_lookup_rec(dir, &dx_root->dr_list,
4424 					      major_hash, &cpos, &blkno, &clen);
4425 		if (ret) {
4426 			mlog_errno(ret);
4427 			goto out;
4428 		}
4429 
4430 		p_cpos = ocfs2_blocks_to_clusters(dir->i_sb, blkno);
4431 
4432 		ret = ocfs2_remove_btree_range(dir, &et, cpos, p_cpos, clen, 0,
4433 					       &dealloc, 0, false);
4434 		if (ret) {
4435 			mlog_errno(ret);
4436 			goto out;
4437 		}
4438 
4439 		if (cpos == 0)
4440 			break;
4441 
4442 		major_hash = cpos - 1;
4443 	}
4444 
4445 remove_index:
4446 	ret = ocfs2_dx_dir_remove_index(dir, di_bh, dx_root_bh);
4447 	if (ret) {
4448 		mlog_errno(ret);
4449 		goto out;
4450 	}
4451 
4452 	ocfs2_remove_from_cache(INODE_CACHE(dir), dx_root_bh);
4453 out:
4454 	ocfs2_schedule_truncate_log_flush(osb, 1);
4455 	ocfs2_run_deallocs(osb, &dealloc);
4456 
4457 	brelse(dx_root_bh);
4458 	return ret;
4459 }
4460