xref: /linux/fs/ocfs2/dir.c (revision f96a974170b749e3a56844e25b31d46a7233b6f6)
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 				 char *buf,
301 				 unsigned int size,
302 				 unsigned long offset)
303 {
304 	const char *error_msg = NULL;
305 	const int rlen = le16_to_cpu(de->rec_len);
306 	const unsigned long next_offset = ((char *) de - buf) + rlen;
307 
308 	if (unlikely(rlen < OCFS2_DIR_REC_LEN(1)))
309 		error_msg = "rec_len is smaller than minimal";
310 	else if (unlikely(rlen % 4 != 0))
311 		error_msg = "rec_len % 4 != 0";
312 	else if (unlikely(rlen < OCFS2_DIR_REC_LEN(de->name_len)))
313 		error_msg = "rec_len is too small for name_len";
314 	else if (unlikely(next_offset > size))
315 		error_msg = "directory entry overrun";
316 	else if (unlikely(next_offset > size - OCFS2_DIR_REC_LEN(1)) &&
317 		 next_offset != size)
318 		error_msg = "directory entry too close to end";
319 
320 	if (unlikely(error_msg != NULL))
321 		mlog(ML_ERROR, "bad entry in directory #%llu: %s - "
322 		     "offset=%lu, inode=%llu, rec_len=%d, name_len=%d\n",
323 		     (unsigned long long)OCFS2_I(dir)->ip_blkno, error_msg,
324 		     offset, (unsigned long long)le64_to_cpu(de->inode), rlen,
325 		     de->name_len);
326 
327 	return error_msg == NULL ? 1 : 0;
328 }
329 
330 static inline int ocfs2_match(int len,
331 			      const char * const name,
332 			      struct ocfs2_dir_entry *de)
333 {
334 	if (len != de->name_len)
335 		return 0;
336 	if (!de->inode)
337 		return 0;
338 	return !memcmp(name, de->name, len);
339 }
340 
341 /*
342  * Returns 0 if not found, -1 on failure, and 1 on success
343  */
344 static inline int ocfs2_search_dirblock(struct buffer_head *bh,
345 					struct inode *dir,
346 					const char *name, int namelen,
347 					unsigned long offset,
348 					char *first_de,
349 					unsigned int bytes,
350 					struct ocfs2_dir_entry **res_dir)
351 {
352 	struct ocfs2_dir_entry *de;
353 	char *dlimit, *de_buf;
354 	int de_len;
355 	int ret = 0;
356 
357 	de_buf = first_de;
358 	dlimit = de_buf + bytes;
359 
360 	while (de_buf < dlimit - OCFS2_DIR_MEMBER_LEN) {
361 		/* this code is executed quadratically often */
362 		/* do minimal checking `by hand' */
363 
364 		de = (struct ocfs2_dir_entry *) de_buf;
365 
366 		if (de->name + namelen <= dlimit &&
367 		    ocfs2_match(namelen, name, de)) {
368 			/* found a match - just to be sure, do a full check */
369 			if (!ocfs2_check_dir_entry(dir, de, bh, first_de,
370 						   bytes, offset)) {
371 				ret = -1;
372 				goto bail;
373 			}
374 			*res_dir = de;
375 			ret = 1;
376 			goto bail;
377 		}
378 
379 		/* prevent looping on a bad block */
380 		de_len = le16_to_cpu(de->rec_len);
381 		if (de_len <= 0) {
382 			ret = -1;
383 			goto bail;
384 		}
385 
386 		de_buf += de_len;
387 		offset += de_len;
388 	}
389 
390 bail:
391 	trace_ocfs2_search_dirblock(ret);
392 	return ret;
393 }
394 
395 static struct buffer_head *ocfs2_find_entry_id(const char *name,
396 					       int namelen,
397 					       struct inode *dir,
398 					       struct ocfs2_dir_entry **res_dir)
399 {
400 	int ret, found;
401 	struct buffer_head *di_bh = NULL;
402 	struct ocfs2_dinode *di;
403 	struct ocfs2_inline_data *data;
404 
405 	ret = ocfs2_read_inode_block(dir, &di_bh);
406 	if (ret) {
407 		mlog_errno(ret);
408 		goto out;
409 	}
410 
411 	di = (struct ocfs2_dinode *)di_bh->b_data;
412 	data = &di->id2.i_data;
413 
414 	found = ocfs2_search_dirblock(di_bh, dir, name, namelen, 0,
415 				      data->id_data, i_size_read(dir), res_dir);
416 	if (found == 1)
417 		return di_bh;
418 
419 	brelse(di_bh);
420 out:
421 	return NULL;
422 }
423 
424 static int ocfs2_validate_dir_block(struct super_block *sb,
425 				    struct buffer_head *bh)
426 {
427 	int rc;
428 	struct ocfs2_dir_block_trailer *trailer =
429 		ocfs2_trailer_from_bh(bh, sb);
430 
431 
432 	/*
433 	 * We don't validate dirents here, that's handled
434 	 * in-place when the code walks them.
435 	 */
436 	trace_ocfs2_validate_dir_block((unsigned long long)bh->b_blocknr);
437 
438 	BUG_ON(!buffer_uptodate(bh));
439 
440 	/*
441 	 * If the ecc fails, we return the error but otherwise
442 	 * leave the filesystem running.  We know any error is
443 	 * local to this block.
444 	 *
445 	 * Note that we are safe to call this even if the directory
446 	 * doesn't have a trailer.  Filesystems without metaecc will do
447 	 * nothing, and filesystems with it will have one.
448 	 */
449 	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &trailer->db_check);
450 	if (rc)
451 		mlog(ML_ERROR, "Checksum failed for dinode %llu\n",
452 		     (unsigned long long)bh->b_blocknr);
453 
454 	return rc;
455 }
456 
457 /*
458  * Validate a directory trailer.
459  *
460  * We check the trailer here rather than in ocfs2_validate_dir_block()
461  * because that function doesn't have the inode to test.
462  */
463 static int ocfs2_check_dir_trailer(struct inode *dir, struct buffer_head *bh)
464 {
465 	int rc = 0;
466 	struct ocfs2_dir_block_trailer *trailer;
467 
468 	trailer = ocfs2_trailer_from_bh(bh, dir->i_sb);
469 	if (!OCFS2_IS_VALID_DIR_TRAILER(trailer)) {
470 		rc = ocfs2_error(dir->i_sb,
471 				 "Invalid dirblock #%llu: signature = %.*s\n",
472 				 (unsigned long long)bh->b_blocknr, 7,
473 				 trailer->db_signature);
474 		goto out;
475 	}
476 	if (le64_to_cpu(trailer->db_blkno) != bh->b_blocknr) {
477 		rc = ocfs2_error(dir->i_sb,
478 				 "Directory block #%llu has an invalid db_blkno of %llu\n",
479 				 (unsigned long long)bh->b_blocknr,
480 				 (unsigned long long)le64_to_cpu(trailer->db_blkno));
481 		goto out;
482 	}
483 	if (le64_to_cpu(trailer->db_parent_dinode) !=
484 	    OCFS2_I(dir)->ip_blkno) {
485 		rc = ocfs2_error(dir->i_sb,
486 				 "Directory block #%llu on dinode #%llu has an invalid parent_dinode of %llu\n",
487 				 (unsigned long long)bh->b_blocknr,
488 				 (unsigned long long)OCFS2_I(dir)->ip_blkno,
489 				 (unsigned long long)le64_to_cpu(trailer->db_blkno));
490 		goto out;
491 	}
492 out:
493 	return rc;
494 }
495 
496 /*
497  * This function forces all errors to -EIO for consistency with its
498  * predecessor, ocfs2_bread().  We haven't audited what returning the
499  * real error codes would do to callers.  We log the real codes with
500  * mlog_errno() before we squash them.
501  */
502 static int ocfs2_read_dir_block(struct inode *inode, u64 v_block,
503 				struct buffer_head **bh, int flags)
504 {
505 	int rc = 0;
506 	struct buffer_head *tmp = *bh;
507 
508 	rc = ocfs2_read_virt_blocks(inode, v_block, 1, &tmp, flags,
509 				    ocfs2_validate_dir_block);
510 	if (rc) {
511 		mlog_errno(rc);
512 		goto out;
513 	}
514 
515 	if (!(flags & OCFS2_BH_READAHEAD) &&
516 	    ocfs2_supports_dir_trailer(inode)) {
517 		rc = ocfs2_check_dir_trailer(inode, tmp);
518 		if (rc) {
519 			if (!*bh)
520 				brelse(tmp);
521 			mlog_errno(rc);
522 			goto out;
523 		}
524 	}
525 
526 	/* If ocfs2_read_virt_blocks() got us a new bh, pass it up. */
527 	if (!*bh)
528 		*bh = tmp;
529 
530 out:
531 	return rc ? -EIO : 0;
532 }
533 
534 /*
535  * Read the block at 'phys' which belongs to this directory
536  * inode. This function does no virtual->physical block translation -
537  * what's passed in is assumed to be a valid directory block.
538  */
539 static int ocfs2_read_dir_block_direct(struct inode *dir, u64 phys,
540 				       struct buffer_head **bh)
541 {
542 	int ret;
543 	struct buffer_head *tmp = *bh;
544 
545 	ret = ocfs2_read_block(INODE_CACHE(dir), phys, &tmp,
546 			       ocfs2_validate_dir_block);
547 	if (ret) {
548 		mlog_errno(ret);
549 		goto out;
550 	}
551 
552 	if (ocfs2_supports_dir_trailer(dir)) {
553 		ret = ocfs2_check_dir_trailer(dir, tmp);
554 		if (ret) {
555 			if (!*bh)
556 				brelse(tmp);
557 			mlog_errno(ret);
558 			goto out;
559 		}
560 	}
561 
562 	if (!ret && !*bh)
563 		*bh = tmp;
564 out:
565 	return ret;
566 }
567 
568 static int ocfs2_validate_dx_root(struct super_block *sb,
569 				  struct buffer_head *bh)
570 {
571 	int ret;
572 	struct ocfs2_dx_root_block *dx_root;
573 
574 	BUG_ON(!buffer_uptodate(bh));
575 
576 	dx_root = (struct ocfs2_dx_root_block *) bh->b_data;
577 
578 	ret = ocfs2_validate_meta_ecc(sb, bh->b_data, &dx_root->dr_check);
579 	if (ret) {
580 		mlog(ML_ERROR,
581 		     "Checksum failed for dir index root block %llu\n",
582 		     (unsigned long long)bh->b_blocknr);
583 		return ret;
584 	}
585 
586 	if (!OCFS2_IS_VALID_DX_ROOT(dx_root)) {
587 		ret = ocfs2_error(sb,
588 				  "Dir Index Root # %llu has bad signature %.*s\n",
589 				  (unsigned long long)le64_to_cpu(dx_root->dr_blkno),
590 				  7, dx_root->dr_signature);
591 	}
592 
593 	return ret;
594 }
595 
596 static int ocfs2_read_dx_root(struct inode *dir, struct ocfs2_dinode *di,
597 			      struct buffer_head **dx_root_bh)
598 {
599 	int ret;
600 	u64 blkno = le64_to_cpu(di->i_dx_root);
601 	struct buffer_head *tmp = *dx_root_bh;
602 
603 	ret = ocfs2_read_block(INODE_CACHE(dir), blkno, &tmp,
604 			       ocfs2_validate_dx_root);
605 
606 	/* If ocfs2_read_block() got us a new bh, pass it up. */
607 	if (!ret && !*dx_root_bh)
608 		*dx_root_bh = tmp;
609 
610 	return ret;
611 }
612 
613 static int ocfs2_validate_dx_leaf(struct super_block *sb,
614 				  struct buffer_head *bh)
615 {
616 	int ret;
617 	struct ocfs2_dx_leaf *dx_leaf = (struct ocfs2_dx_leaf *)bh->b_data;
618 
619 	BUG_ON(!buffer_uptodate(bh));
620 
621 	ret = ocfs2_validate_meta_ecc(sb, bh->b_data, &dx_leaf->dl_check);
622 	if (ret) {
623 		mlog(ML_ERROR,
624 		     "Checksum failed for dir index leaf block %llu\n",
625 		     (unsigned long long)bh->b_blocknr);
626 		return ret;
627 	}
628 
629 	if (!OCFS2_IS_VALID_DX_LEAF(dx_leaf)) {
630 		ret = ocfs2_error(sb, "Dir Index Leaf has bad signature %.*s\n",
631 				  7, dx_leaf->dl_signature);
632 	}
633 
634 	return ret;
635 }
636 
637 static int ocfs2_read_dx_leaf(struct inode *dir, u64 blkno,
638 			      struct buffer_head **dx_leaf_bh)
639 {
640 	int ret;
641 	struct buffer_head *tmp = *dx_leaf_bh;
642 
643 	ret = ocfs2_read_block(INODE_CACHE(dir), blkno, &tmp,
644 			       ocfs2_validate_dx_leaf);
645 
646 	/* If ocfs2_read_block() got us a new bh, pass it up. */
647 	if (!ret && !*dx_leaf_bh)
648 		*dx_leaf_bh = tmp;
649 
650 	return ret;
651 }
652 
653 /*
654  * Read a series of dx_leaf blocks. This expects all buffer_head
655  * pointers to be NULL on function entry.
656  */
657 static int ocfs2_read_dx_leaves(struct inode *dir, u64 start, int num,
658 				struct buffer_head **dx_leaf_bhs)
659 {
660 	int ret;
661 
662 	ret = ocfs2_read_blocks(INODE_CACHE(dir), start, num, dx_leaf_bhs, 0,
663 				ocfs2_validate_dx_leaf);
664 	if (ret)
665 		mlog_errno(ret);
666 
667 	return ret;
668 }
669 
670 static struct buffer_head *ocfs2_find_entry_el(const char *name, int namelen,
671 					       struct inode *dir,
672 					       struct ocfs2_dir_entry **res_dir)
673 {
674 	struct super_block *sb;
675 	struct buffer_head *bh_use[NAMEI_RA_SIZE];
676 	struct buffer_head *bh, *ret = NULL;
677 	unsigned long start, block, b;
678 	int ra_max = 0;		/* Number of bh's in the readahead
679 				   buffer, bh_use[] */
680 	int ra_ptr = 0;		/* Current index into readahead
681 				   buffer */
682 	int num = 0;
683 	int nblocks, i;
684 
685 	sb = dir->i_sb;
686 
687 	nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
688 	start = OCFS2_I(dir)->ip_dir_start_lookup;
689 	if (start >= nblocks)
690 		start = 0;
691 	block = start;
692 
693 restart:
694 	do {
695 		/*
696 		 * We deal with the read-ahead logic here.
697 		 */
698 		if (ra_ptr >= ra_max) {
699 			/* Refill the readahead buffer */
700 			ra_ptr = 0;
701 			b = block;
702 			for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
703 				/*
704 				 * Terminate if we reach the end of the
705 				 * directory and must wrap, or if our
706 				 * search has finished at this block.
707 				 */
708 				if (b >= nblocks || (num && block == start)) {
709 					bh_use[ra_max] = NULL;
710 					break;
711 				}
712 				num++;
713 
714 				bh = NULL;
715 				ocfs2_read_dir_block(dir, b++, &bh,
716 							   OCFS2_BH_READAHEAD);
717 				bh_use[ra_max] = bh;
718 			}
719 		}
720 		if ((bh = bh_use[ra_ptr++]) == NULL)
721 			goto next;
722 		if (ocfs2_read_dir_block(dir, block, &bh, 0)) {
723 			/* read error, skip block & hope for the best.
724 			 * ocfs2_read_dir_block() has released the bh. */
725 			mlog(ML_ERROR, "reading directory %llu, "
726 				    "offset %lu\n",
727 				    (unsigned long long)OCFS2_I(dir)->ip_blkno,
728 				    block);
729 			goto next;
730 		}
731 		i = ocfs2_search_dirblock(bh, dir, name, namelen,
732 					  block << sb->s_blocksize_bits,
733 					  bh->b_data, sb->s_blocksize,
734 					  res_dir);
735 		if (i == 1) {
736 			OCFS2_I(dir)->ip_dir_start_lookup = block;
737 			ret = bh;
738 			goto cleanup_and_exit;
739 		} else {
740 			brelse(bh);
741 			if (i < 0)
742 				goto cleanup_and_exit;
743 		}
744 	next:
745 		if (++block >= nblocks)
746 			block = 0;
747 	} while (block != start);
748 
749 	/*
750 	 * If the directory has grown while we were searching, then
751 	 * search the last part of the directory before giving up.
752 	 */
753 	block = nblocks;
754 	nblocks = i_size_read(dir) >> sb->s_blocksize_bits;
755 	if (block < nblocks) {
756 		start = 0;
757 		goto restart;
758 	}
759 
760 cleanup_and_exit:
761 	/* Clean up the read-ahead blocks */
762 	for (; ra_ptr < ra_max; ra_ptr++)
763 		brelse(bh_use[ra_ptr]);
764 
765 	trace_ocfs2_find_entry_el(ret);
766 	return ret;
767 }
768 
769 static int ocfs2_dx_dir_lookup_rec(struct inode *inode,
770 				   struct ocfs2_extent_list *el,
771 				   u32 major_hash,
772 				   u32 *ret_cpos,
773 				   u64 *ret_phys_blkno,
774 				   unsigned int *ret_clen)
775 {
776 	int ret = 0, i, found;
777 	struct buffer_head *eb_bh = NULL;
778 	struct ocfs2_extent_block *eb;
779 	struct ocfs2_extent_rec *rec = NULL;
780 
781 	if (el->l_tree_depth) {
782 		ret = ocfs2_find_leaf(INODE_CACHE(inode), el, major_hash,
783 				      &eb_bh);
784 		if (ret) {
785 			mlog_errno(ret);
786 			goto out;
787 		}
788 
789 		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
790 		el = &eb->h_list;
791 
792 		if (el->l_tree_depth) {
793 			ret = ocfs2_error(inode->i_sb,
794 					  "Inode %lu has non zero tree depth in btree tree block %llu\n",
795 					  inode->i_ino,
796 					  (unsigned long long)eb_bh->b_blocknr);
797 			goto out;
798 		}
799 	}
800 
801 	found = 0;
802 	for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
803 		rec = &el->l_recs[i];
804 
805 		if (le32_to_cpu(rec->e_cpos) <= major_hash) {
806 			found = 1;
807 			break;
808 		}
809 	}
810 
811 	if (!found) {
812 		ret = ocfs2_error(inode->i_sb,
813 				  "Inode %lu has bad extent record (%u, %u, 0) in btree\n",
814 				  inode->i_ino,
815 				  le32_to_cpu(rec->e_cpos),
816 				  ocfs2_rec_clusters(el, rec));
817 		goto out;
818 	}
819 
820 	if (ret_phys_blkno)
821 		*ret_phys_blkno = le64_to_cpu(rec->e_blkno);
822 	if (ret_cpos)
823 		*ret_cpos = le32_to_cpu(rec->e_cpos);
824 	if (ret_clen)
825 		*ret_clen = le16_to_cpu(rec->e_leaf_clusters);
826 
827 out:
828 	brelse(eb_bh);
829 	return ret;
830 }
831 
832 /*
833  * Returns the block index, from the start of the cluster which this
834  * hash belongs too.
835  */
836 static inline unsigned int __ocfs2_dx_dir_hash_idx(struct ocfs2_super *osb,
837 						   u32 minor_hash)
838 {
839 	return minor_hash & osb->osb_dx_mask;
840 }
841 
842 static inline unsigned int ocfs2_dx_dir_hash_idx(struct ocfs2_super *osb,
843 					  struct ocfs2_dx_hinfo *hinfo)
844 {
845 	return __ocfs2_dx_dir_hash_idx(osb, hinfo->minor_hash);
846 }
847 
848 static int ocfs2_dx_dir_lookup(struct inode *inode,
849 			       struct ocfs2_extent_list *el,
850 			       struct ocfs2_dx_hinfo *hinfo,
851 			       u32 *ret_cpos,
852 			       u64 *ret_phys_blkno)
853 {
854 	int ret = 0;
855 	unsigned int cend, clen;
856 	u32 cpos;
857 	u64 blkno;
858 	u32 name_hash = hinfo->major_hash;
859 
860 	ret = ocfs2_dx_dir_lookup_rec(inode, el, name_hash, &cpos, &blkno,
861 				      &clen);
862 	if (ret) {
863 		mlog_errno(ret);
864 		goto out;
865 	}
866 
867 	cend = cpos + clen;
868 	if (name_hash >= cend) {
869 		/* We want the last cluster */
870 		blkno += ocfs2_clusters_to_blocks(inode->i_sb, clen - 1);
871 		cpos += clen - 1;
872 	} else {
873 		blkno += ocfs2_clusters_to_blocks(inode->i_sb,
874 						  name_hash - cpos);
875 		cpos = name_hash;
876 	}
877 
878 	/*
879 	 * We now have the cluster which should hold our entry. To
880 	 * find the exact block from the start of the cluster to
881 	 * search, we take the lower bits of the hash.
882 	 */
883 	blkno += ocfs2_dx_dir_hash_idx(OCFS2_SB(inode->i_sb), hinfo);
884 
885 	if (ret_phys_blkno)
886 		*ret_phys_blkno = blkno;
887 	if (ret_cpos)
888 		*ret_cpos = cpos;
889 
890 out:
891 
892 	return ret;
893 }
894 
895 static int ocfs2_dx_dir_search(const char *name, int namelen,
896 			       struct inode *dir,
897 			       struct ocfs2_dx_root_block *dx_root,
898 			       struct ocfs2_dir_lookup_result *res)
899 {
900 	int ret, i, found;
901 	u64 phys;
902 	struct buffer_head *dx_leaf_bh = NULL;
903 	struct ocfs2_dx_leaf *dx_leaf;
904 	struct ocfs2_dx_entry *dx_entry = NULL;
905 	struct buffer_head *dir_ent_bh = NULL;
906 	struct ocfs2_dir_entry *dir_ent = NULL;
907 	struct ocfs2_dx_hinfo *hinfo = &res->dl_hinfo;
908 	struct ocfs2_extent_list *dr_el;
909 	struct ocfs2_dx_entry_list *entry_list;
910 
911 	ocfs2_dx_dir_name_hash(dir, name, namelen, &res->dl_hinfo);
912 
913 	if (ocfs2_dx_root_inline(dx_root)) {
914 		entry_list = &dx_root->dr_entries;
915 		goto search;
916 	}
917 
918 	dr_el = &dx_root->dr_list;
919 
920 	ret = ocfs2_dx_dir_lookup(dir, dr_el, hinfo, NULL, &phys);
921 	if (ret) {
922 		mlog_errno(ret);
923 		goto out;
924 	}
925 
926 	trace_ocfs2_dx_dir_search((unsigned long long)OCFS2_I(dir)->ip_blkno,
927 				  namelen, name, hinfo->major_hash,
928 				  hinfo->minor_hash, (unsigned long long)phys);
929 
930 	ret = ocfs2_read_dx_leaf(dir, phys, &dx_leaf_bh);
931 	if (ret) {
932 		mlog_errno(ret);
933 		goto out;
934 	}
935 
936 	dx_leaf = (struct ocfs2_dx_leaf *) dx_leaf_bh->b_data;
937 
938 	trace_ocfs2_dx_dir_search_leaf_info(
939 			le16_to_cpu(dx_leaf->dl_list.de_num_used),
940 			le16_to_cpu(dx_leaf->dl_list.de_count));
941 
942 	entry_list = &dx_leaf->dl_list;
943 
944 search:
945 	/*
946 	 * Empty leaf is legal, so no need to check for that.
947 	 */
948 	found = 0;
949 	for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) {
950 		dx_entry = &entry_list->de_entries[i];
951 
952 		if (hinfo->major_hash != le32_to_cpu(dx_entry->dx_major_hash)
953 		    || hinfo->minor_hash != le32_to_cpu(dx_entry->dx_minor_hash))
954 			continue;
955 
956 		/*
957 		 * Search unindexed leaf block now. We're not
958 		 * guaranteed to find anything.
959 		 */
960 		ret = ocfs2_read_dir_block_direct(dir,
961 					  le64_to_cpu(dx_entry->dx_dirent_blk),
962 					  &dir_ent_bh);
963 		if (ret) {
964 			mlog_errno(ret);
965 			goto out;
966 		}
967 
968 		/*
969 		 * XXX: We should check the unindexed block here,
970 		 * before using it.
971 		 */
972 
973 		found = ocfs2_search_dirblock(dir_ent_bh, dir, name, namelen,
974 					      0, dir_ent_bh->b_data,
975 					      dir->i_sb->s_blocksize, &dir_ent);
976 		if (found == 1)
977 			break;
978 
979 		if (found == -1) {
980 			/* This means we found a bad directory entry. */
981 			ret = -EIO;
982 			mlog_errno(ret);
983 			goto out;
984 		}
985 
986 		brelse(dir_ent_bh);
987 		dir_ent_bh = NULL;
988 	}
989 
990 	if (found <= 0) {
991 		ret = -ENOENT;
992 		goto out;
993 	}
994 
995 	res->dl_leaf_bh = dir_ent_bh;
996 	res->dl_entry = dir_ent;
997 	res->dl_dx_leaf_bh = dx_leaf_bh;
998 	res->dl_dx_entry = dx_entry;
999 
1000 	ret = 0;
1001 out:
1002 	if (ret) {
1003 		brelse(dx_leaf_bh);
1004 		brelse(dir_ent_bh);
1005 	}
1006 	return ret;
1007 }
1008 
1009 static int ocfs2_find_entry_dx(const char *name, int namelen,
1010 			       struct inode *dir,
1011 			       struct ocfs2_dir_lookup_result *lookup)
1012 {
1013 	int ret;
1014 	struct buffer_head *di_bh = NULL;
1015 	struct ocfs2_dinode *di;
1016 	struct buffer_head *dx_root_bh = NULL;
1017 	struct ocfs2_dx_root_block *dx_root;
1018 
1019 	ret = ocfs2_read_inode_block(dir, &di_bh);
1020 	if (ret) {
1021 		mlog_errno(ret);
1022 		goto out;
1023 	}
1024 
1025 	di = (struct ocfs2_dinode *)di_bh->b_data;
1026 
1027 	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
1028 	if (ret) {
1029 		mlog_errno(ret);
1030 		goto out;
1031 	}
1032 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
1033 
1034 	ret = ocfs2_dx_dir_search(name, namelen, dir, dx_root, lookup);
1035 	if (ret) {
1036 		if (ret != -ENOENT)
1037 			mlog_errno(ret);
1038 		goto out;
1039 	}
1040 
1041 	lookup->dl_dx_root_bh = dx_root_bh;
1042 	dx_root_bh = NULL;
1043 out:
1044 	brelse(di_bh);
1045 	brelse(dx_root_bh);
1046 	return ret;
1047 }
1048 
1049 /*
1050  * Try to find an entry of the provided name within 'dir'.
1051  *
1052  * If nothing was found, -ENOENT is returned. Otherwise, zero is
1053  * returned and the struct 'res' will contain information useful to
1054  * other directory manipulation functions.
1055  *
1056  * Caller can NOT assume anything about the contents of the
1057  * buffer_heads - they are passed back only so that it can be passed
1058  * into any one of the manipulation functions (add entry, delete
1059  * entry, etc). As an example, bh in the extent directory case is a
1060  * data block, in the inline-data case it actually points to an inode,
1061  * in the indexed directory case, multiple buffers are involved.
1062  */
1063 int ocfs2_find_entry(const char *name, int namelen,
1064 		     struct inode *dir, struct ocfs2_dir_lookup_result *lookup)
1065 {
1066 	struct buffer_head *bh;
1067 	struct ocfs2_dir_entry *res_dir = NULL;
1068 	int ret = 0;
1069 
1070 	if (ocfs2_dir_indexed(dir))
1071 		return ocfs2_find_entry_dx(name, namelen, dir, lookup);
1072 
1073 	if (unlikely(i_size_read(dir) <= 0)) {
1074 		ret = -EFSCORRUPTED;
1075 		mlog_errno(ret);
1076 		goto out;
1077 	}
1078 	/*
1079 	 * The unindexed dir code only uses part of the lookup
1080 	 * structure, so there's no reason to push it down further
1081 	 * than this.
1082 	 */
1083 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1084 		if (unlikely(i_size_read(dir) > dir->i_sb->s_blocksize)) {
1085 			ret = -EFSCORRUPTED;
1086 			mlog_errno(ret);
1087 			goto out;
1088 		}
1089 		bh = ocfs2_find_entry_id(name, namelen, dir, &res_dir);
1090 	} else {
1091 		bh = ocfs2_find_entry_el(name, namelen, dir, &res_dir);
1092 	}
1093 
1094 	if (bh == NULL)
1095 		return -ENOENT;
1096 
1097 	lookup->dl_leaf_bh = bh;
1098 	lookup->dl_entry = res_dir;
1099 out:
1100 	return ret;
1101 }
1102 
1103 /*
1104  * Update inode number and type of a previously found directory entry.
1105  */
1106 int ocfs2_update_entry(struct inode *dir, handle_t *handle,
1107 		       struct ocfs2_dir_lookup_result *res,
1108 		       struct inode *new_entry_inode)
1109 {
1110 	int ret;
1111 	ocfs2_journal_access_func access = ocfs2_journal_access_db;
1112 	struct ocfs2_dir_entry *de = res->dl_entry;
1113 	struct buffer_head *de_bh = res->dl_leaf_bh;
1114 
1115 	/*
1116 	 * The same code works fine for both inline-data and extent
1117 	 * based directories, so no need to split this up.  The only
1118 	 * difference is the journal_access function.
1119 	 */
1120 
1121 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1122 		access = ocfs2_journal_access_di;
1123 
1124 	ret = access(handle, INODE_CACHE(dir), de_bh,
1125 		     OCFS2_JOURNAL_ACCESS_WRITE);
1126 	if (ret) {
1127 		mlog_errno(ret);
1128 		goto out;
1129 	}
1130 
1131 	de->inode = cpu_to_le64(OCFS2_I(new_entry_inode)->ip_blkno);
1132 	ocfs2_set_de_type(de, new_entry_inode->i_mode);
1133 
1134 	ocfs2_journal_dirty(handle, de_bh);
1135 
1136 out:
1137 	return ret;
1138 }
1139 
1140 /*
1141  * __ocfs2_delete_entry deletes a directory entry by merging it with the
1142  * previous entry
1143  */
1144 static int __ocfs2_delete_entry(handle_t *handle, struct inode *dir,
1145 				struct ocfs2_dir_entry *de_del,
1146 				struct buffer_head *bh, char *first_de,
1147 				unsigned int bytes)
1148 {
1149 	struct ocfs2_dir_entry *de, *pde;
1150 	int i, status = -ENOENT;
1151 	ocfs2_journal_access_func access = ocfs2_journal_access_db;
1152 
1153 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1154 		access = ocfs2_journal_access_di;
1155 
1156 	i = 0;
1157 	pde = NULL;
1158 	de = (struct ocfs2_dir_entry *) first_de;
1159 	while (i < bytes) {
1160 		if (!ocfs2_check_dir_entry(dir, de, bh, first_de, bytes, i)) {
1161 			status = -EIO;
1162 			mlog_errno(status);
1163 			goto bail;
1164 		}
1165 		if (de == de_del)  {
1166 			status = access(handle, INODE_CACHE(dir), bh,
1167 					OCFS2_JOURNAL_ACCESS_WRITE);
1168 			if (status < 0) {
1169 				status = -EIO;
1170 				mlog_errno(status);
1171 				goto bail;
1172 			}
1173 			if (pde)
1174 				le16_add_cpu(&pde->rec_len,
1175 						le16_to_cpu(de->rec_len));
1176 			de->inode = 0;
1177 			inode_inc_iversion(dir);
1178 			ocfs2_journal_dirty(handle, bh);
1179 			goto bail;
1180 		}
1181 		i += le16_to_cpu(de->rec_len);
1182 		pde = de;
1183 		de = (struct ocfs2_dir_entry *)((char *)de + le16_to_cpu(de->rec_len));
1184 	}
1185 bail:
1186 	return status;
1187 }
1188 
1189 static unsigned int ocfs2_figure_dirent_hole(struct ocfs2_dir_entry *de)
1190 {
1191 	unsigned int hole;
1192 
1193 	if (le64_to_cpu(de->inode) == 0)
1194 		hole = le16_to_cpu(de->rec_len);
1195 	else
1196 		hole = le16_to_cpu(de->rec_len) -
1197 			OCFS2_DIR_REC_LEN(de->name_len);
1198 
1199 	return hole;
1200 }
1201 
1202 static int ocfs2_find_max_rec_len(struct super_block *sb,
1203 				  struct buffer_head *dirblock_bh)
1204 {
1205 	int size, this_hole, largest_hole = 0;
1206 	char *trailer, *de_buf, *limit, *start = dirblock_bh->b_data;
1207 	struct ocfs2_dir_entry *de;
1208 
1209 	trailer = (char *)ocfs2_trailer_from_bh(dirblock_bh, sb);
1210 	size = ocfs2_dir_trailer_blk_off(sb);
1211 	limit = start + size;
1212 	de_buf = start;
1213 	de = (struct ocfs2_dir_entry *)de_buf;
1214 	do {
1215 		if (de_buf != trailer) {
1216 			this_hole = ocfs2_figure_dirent_hole(de);
1217 			if (this_hole > largest_hole)
1218 				largest_hole = this_hole;
1219 		}
1220 
1221 		de_buf += le16_to_cpu(de->rec_len);
1222 		de = (struct ocfs2_dir_entry *)de_buf;
1223 	} while (de_buf < limit);
1224 
1225 	if (largest_hole >= OCFS2_DIR_MIN_REC_LEN)
1226 		return largest_hole;
1227 	return 0;
1228 }
1229 
1230 static void ocfs2_dx_list_remove_entry(struct ocfs2_dx_entry_list *entry_list,
1231 				       int index)
1232 {
1233 	int num_used = le16_to_cpu(entry_list->de_num_used);
1234 
1235 	if (num_used == 1 || index == (num_used - 1))
1236 		goto clear;
1237 
1238 	memmove(&entry_list->de_entries[index],
1239 		&entry_list->de_entries[index + 1],
1240 		(num_used - index - 1)*sizeof(struct ocfs2_dx_entry));
1241 clear:
1242 	num_used--;
1243 	memset(&entry_list->de_entries[num_used], 0,
1244 	       sizeof(struct ocfs2_dx_entry));
1245 	entry_list->de_num_used = cpu_to_le16(num_used);
1246 }
1247 
1248 static int ocfs2_delete_entry_dx(handle_t *handle, struct inode *dir,
1249 				 struct ocfs2_dir_lookup_result *lookup)
1250 {
1251 	int ret, index, max_rec_len, add_to_free_list = 0;
1252 	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
1253 	struct buffer_head *leaf_bh = lookup->dl_leaf_bh;
1254 	struct ocfs2_dx_leaf *dx_leaf;
1255 	struct ocfs2_dx_entry *dx_entry = lookup->dl_dx_entry;
1256 	struct ocfs2_dir_block_trailer *trailer;
1257 	struct ocfs2_dx_root_block *dx_root;
1258 	struct ocfs2_dx_entry_list *entry_list;
1259 
1260 	/*
1261 	 * This function gets a bit messy because we might have to
1262 	 * modify the root block, regardless of whether the indexed
1263 	 * entries are stored inline.
1264 	 */
1265 
1266 	/*
1267 	 * *Only* set 'entry_list' here, based on where we're looking
1268 	 * for the indexed entries. Later, we might still want to
1269 	 * journal both blocks, based on free list state.
1270 	 */
1271 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
1272 	if (ocfs2_dx_root_inline(dx_root)) {
1273 		entry_list = &dx_root->dr_entries;
1274 	} else {
1275 		dx_leaf = (struct ocfs2_dx_leaf *) lookup->dl_dx_leaf_bh->b_data;
1276 		entry_list = &dx_leaf->dl_list;
1277 	}
1278 
1279 	/* Neither of these are a disk corruption - that should have
1280 	 * been caught by lookup, before we got here. */
1281 	BUG_ON(le16_to_cpu(entry_list->de_count) <= 0);
1282 	BUG_ON(le16_to_cpu(entry_list->de_num_used) <= 0);
1283 
1284 	index = (char *)dx_entry - (char *)entry_list->de_entries;
1285 	index /= sizeof(*dx_entry);
1286 
1287 	if (index >= le16_to_cpu(entry_list->de_num_used)) {
1288 		mlog(ML_ERROR, "Dir %llu: Bad dx_entry ptr idx %d, (%p, %p)\n",
1289 		     (unsigned long long)OCFS2_I(dir)->ip_blkno, index,
1290 		     entry_list, dx_entry);
1291 		return -EIO;
1292 	}
1293 
1294 	/*
1295 	 * We know that removal of this dirent will leave enough room
1296 	 * for a new one, so add this block to the free list if it
1297 	 * isn't already there.
1298 	 */
1299 	trailer = ocfs2_trailer_from_bh(leaf_bh, dir->i_sb);
1300 	if (trailer->db_free_rec_len == 0)
1301 		add_to_free_list = 1;
1302 
1303 	/*
1304 	 * Add the block holding our index into the journal before
1305 	 * removing the unindexed entry. If we get an error return
1306 	 * from __ocfs2_delete_entry(), then it hasn't removed the
1307 	 * entry yet. Likewise, successful return means we *must*
1308 	 * remove the indexed entry.
1309 	 *
1310 	 * We're also careful to journal the root tree block here as
1311 	 * the entry count needs to be updated. Also, we might be
1312 	 * adding to the start of the free list.
1313 	 */
1314 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
1315 				      OCFS2_JOURNAL_ACCESS_WRITE);
1316 	if (ret) {
1317 		mlog_errno(ret);
1318 		goto out;
1319 	}
1320 
1321 	if (!ocfs2_dx_root_inline(dx_root)) {
1322 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
1323 					      lookup->dl_dx_leaf_bh,
1324 					      OCFS2_JOURNAL_ACCESS_WRITE);
1325 		if (ret) {
1326 			mlog_errno(ret);
1327 			goto out;
1328 		}
1329 	}
1330 
1331 	trace_ocfs2_delete_entry_dx((unsigned long long)OCFS2_I(dir)->ip_blkno,
1332 				    index);
1333 
1334 	ret = __ocfs2_delete_entry(handle, dir, lookup->dl_entry,
1335 				   leaf_bh, leaf_bh->b_data, leaf_bh->b_size);
1336 	if (ret) {
1337 		mlog_errno(ret);
1338 		goto out;
1339 	}
1340 
1341 	max_rec_len = ocfs2_find_max_rec_len(dir->i_sb, leaf_bh);
1342 	trailer->db_free_rec_len = cpu_to_le16(max_rec_len);
1343 	if (add_to_free_list) {
1344 		trailer->db_free_next = dx_root->dr_free_blk;
1345 		dx_root->dr_free_blk = cpu_to_le64(leaf_bh->b_blocknr);
1346 		ocfs2_journal_dirty(handle, dx_root_bh);
1347 	}
1348 
1349 	/* leaf_bh was journal_accessed for us in __ocfs2_delete_entry */
1350 	ocfs2_journal_dirty(handle, leaf_bh);
1351 
1352 	le32_add_cpu(&dx_root->dr_num_entries, -1);
1353 	ocfs2_journal_dirty(handle, dx_root_bh);
1354 
1355 	ocfs2_dx_list_remove_entry(entry_list, index);
1356 
1357 	if (!ocfs2_dx_root_inline(dx_root))
1358 		ocfs2_journal_dirty(handle, lookup->dl_dx_leaf_bh);
1359 
1360 out:
1361 	return ret;
1362 }
1363 
1364 static inline int ocfs2_delete_entry_id(handle_t *handle,
1365 					struct inode *dir,
1366 					struct ocfs2_dir_entry *de_del,
1367 					struct buffer_head *bh)
1368 {
1369 	int ret;
1370 	struct buffer_head *di_bh = NULL;
1371 	struct ocfs2_dinode *di;
1372 	struct ocfs2_inline_data *data;
1373 
1374 	ret = ocfs2_read_inode_block(dir, &di_bh);
1375 	if (ret) {
1376 		mlog_errno(ret);
1377 		goto out;
1378 	}
1379 
1380 	di = (struct ocfs2_dinode *)di_bh->b_data;
1381 	data = &di->id2.i_data;
1382 
1383 	ret = __ocfs2_delete_entry(handle, dir, de_del, bh, data->id_data,
1384 				   i_size_read(dir));
1385 
1386 	brelse(di_bh);
1387 out:
1388 	return ret;
1389 }
1390 
1391 static inline int ocfs2_delete_entry_el(handle_t *handle,
1392 					struct inode *dir,
1393 					struct ocfs2_dir_entry *de_del,
1394 					struct buffer_head *bh)
1395 {
1396 	return __ocfs2_delete_entry(handle, dir, de_del, bh, bh->b_data,
1397 				    bh->b_size);
1398 }
1399 
1400 /*
1401  * Delete a directory entry. Hide the details of directory
1402  * implementation from the caller.
1403  */
1404 int ocfs2_delete_entry(handle_t *handle,
1405 		       struct inode *dir,
1406 		       struct ocfs2_dir_lookup_result *res)
1407 {
1408 	if (ocfs2_dir_indexed(dir))
1409 		return ocfs2_delete_entry_dx(handle, dir, res);
1410 
1411 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1412 		return ocfs2_delete_entry_id(handle, dir, res->dl_entry,
1413 					     res->dl_leaf_bh);
1414 
1415 	return ocfs2_delete_entry_el(handle, dir, res->dl_entry,
1416 				     res->dl_leaf_bh);
1417 }
1418 
1419 /*
1420  * Check whether 'de' has enough room to hold an entry of
1421  * 'new_rec_len' bytes.
1422  */
1423 static inline int ocfs2_dirent_would_fit(struct ocfs2_dir_entry *de,
1424 					 unsigned int new_rec_len)
1425 {
1426 	unsigned int de_really_used;
1427 
1428 	/* Check whether this is an empty record with enough space */
1429 	if (le64_to_cpu(de->inode) == 0 &&
1430 	    le16_to_cpu(de->rec_len) >= new_rec_len)
1431 		return 1;
1432 
1433 	/*
1434 	 * Record might have free space at the end which we can
1435 	 * use.
1436 	 */
1437 	de_really_used = OCFS2_DIR_REC_LEN(de->name_len);
1438 	if (le16_to_cpu(de->rec_len) >= (de_really_used + new_rec_len))
1439 	    return 1;
1440 
1441 	return 0;
1442 }
1443 
1444 static void ocfs2_dx_dir_leaf_insert_tail(struct ocfs2_dx_leaf *dx_leaf,
1445 					  struct ocfs2_dx_entry *dx_new_entry)
1446 {
1447 	int i;
1448 
1449 	i = le16_to_cpu(dx_leaf->dl_list.de_num_used);
1450 	dx_leaf->dl_list.de_entries[i] = *dx_new_entry;
1451 
1452 	le16_add_cpu(&dx_leaf->dl_list.de_num_used, 1);
1453 }
1454 
1455 static void ocfs2_dx_entry_list_insert(struct ocfs2_dx_entry_list *entry_list,
1456 				       struct ocfs2_dx_hinfo *hinfo,
1457 				       u64 dirent_blk)
1458 {
1459 	int i;
1460 	struct ocfs2_dx_entry *dx_entry;
1461 
1462 	i = le16_to_cpu(entry_list->de_num_used);
1463 	dx_entry = &entry_list->de_entries[i];
1464 
1465 	memset(dx_entry, 0, sizeof(*dx_entry));
1466 	dx_entry->dx_major_hash = cpu_to_le32(hinfo->major_hash);
1467 	dx_entry->dx_minor_hash = cpu_to_le32(hinfo->minor_hash);
1468 	dx_entry->dx_dirent_blk = cpu_to_le64(dirent_blk);
1469 
1470 	le16_add_cpu(&entry_list->de_num_used, 1);
1471 }
1472 
1473 static int __ocfs2_dx_dir_leaf_insert(struct inode *dir, handle_t *handle,
1474 				      struct ocfs2_dx_hinfo *hinfo,
1475 				      u64 dirent_blk,
1476 				      struct buffer_head *dx_leaf_bh)
1477 {
1478 	int ret;
1479 	struct ocfs2_dx_leaf *dx_leaf;
1480 
1481 	ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), dx_leaf_bh,
1482 				      OCFS2_JOURNAL_ACCESS_WRITE);
1483 	if (ret) {
1484 		mlog_errno(ret);
1485 		goto out;
1486 	}
1487 
1488 	dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
1489 	ocfs2_dx_entry_list_insert(&dx_leaf->dl_list, hinfo, dirent_blk);
1490 	ocfs2_journal_dirty(handle, dx_leaf_bh);
1491 
1492 out:
1493 	return ret;
1494 }
1495 
1496 static void ocfs2_dx_inline_root_insert(struct inode *dir, handle_t *handle,
1497 					struct ocfs2_dx_hinfo *hinfo,
1498 					u64 dirent_blk,
1499 					struct ocfs2_dx_root_block *dx_root)
1500 {
1501 	ocfs2_dx_entry_list_insert(&dx_root->dr_entries, hinfo, dirent_blk);
1502 }
1503 
1504 static int ocfs2_dx_dir_insert(struct inode *dir, handle_t *handle,
1505 			       struct ocfs2_dir_lookup_result *lookup)
1506 {
1507 	int ret = 0;
1508 	struct ocfs2_dx_root_block *dx_root;
1509 	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
1510 
1511 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
1512 				      OCFS2_JOURNAL_ACCESS_WRITE);
1513 	if (ret) {
1514 		mlog_errno(ret);
1515 		goto out;
1516 	}
1517 
1518 	dx_root = (struct ocfs2_dx_root_block *)lookup->dl_dx_root_bh->b_data;
1519 	if (ocfs2_dx_root_inline(dx_root)) {
1520 		ocfs2_dx_inline_root_insert(dir, handle,
1521 					    &lookup->dl_hinfo,
1522 					    lookup->dl_leaf_bh->b_blocknr,
1523 					    dx_root);
1524 	} else {
1525 		ret = __ocfs2_dx_dir_leaf_insert(dir, handle, &lookup->dl_hinfo,
1526 						 lookup->dl_leaf_bh->b_blocknr,
1527 						 lookup->dl_dx_leaf_bh);
1528 		if (ret)
1529 			goto out;
1530 	}
1531 
1532 	le32_add_cpu(&dx_root->dr_num_entries, 1);
1533 	ocfs2_journal_dirty(handle, dx_root_bh);
1534 
1535 out:
1536 	return ret;
1537 }
1538 
1539 static void ocfs2_remove_block_from_free_list(struct inode *dir,
1540 				       handle_t *handle,
1541 				       struct ocfs2_dir_lookup_result *lookup)
1542 {
1543 	struct ocfs2_dir_block_trailer *trailer, *prev;
1544 	struct ocfs2_dx_root_block *dx_root;
1545 	struct buffer_head *bh;
1546 
1547 	trailer = ocfs2_trailer_from_bh(lookup->dl_leaf_bh, dir->i_sb);
1548 
1549 	if (ocfs2_free_list_at_root(lookup)) {
1550 		bh = lookup->dl_dx_root_bh;
1551 		dx_root = (struct ocfs2_dx_root_block *)bh->b_data;
1552 		dx_root->dr_free_blk = trailer->db_free_next;
1553 	} else {
1554 		bh = lookup->dl_prev_leaf_bh;
1555 		prev = ocfs2_trailer_from_bh(bh, dir->i_sb);
1556 		prev->db_free_next = trailer->db_free_next;
1557 	}
1558 
1559 	trailer->db_free_rec_len = cpu_to_le16(0);
1560 	trailer->db_free_next = cpu_to_le64(0);
1561 
1562 	ocfs2_journal_dirty(handle, bh);
1563 	ocfs2_journal_dirty(handle, lookup->dl_leaf_bh);
1564 }
1565 
1566 /*
1567  * This expects that a journal write has been reserved on
1568  * lookup->dl_prev_leaf_bh or lookup->dl_dx_root_bh
1569  */
1570 static void ocfs2_recalc_free_list(struct inode *dir, handle_t *handle,
1571 				   struct ocfs2_dir_lookup_result *lookup)
1572 {
1573 	int max_rec_len;
1574 	struct ocfs2_dir_block_trailer *trailer;
1575 
1576 	/* Walk dl_leaf_bh to figure out what the new free rec_len is. */
1577 	max_rec_len = ocfs2_find_max_rec_len(dir->i_sb, lookup->dl_leaf_bh);
1578 	if (max_rec_len) {
1579 		/*
1580 		 * There's still room in this block, so no need to remove it
1581 		 * from the free list. In this case, we just want to update
1582 		 * the rec len accounting.
1583 		 */
1584 		trailer = ocfs2_trailer_from_bh(lookup->dl_leaf_bh, dir->i_sb);
1585 		trailer->db_free_rec_len = cpu_to_le16(max_rec_len);
1586 		ocfs2_journal_dirty(handle, lookup->dl_leaf_bh);
1587 	} else {
1588 		ocfs2_remove_block_from_free_list(dir, handle, lookup);
1589 	}
1590 }
1591 
1592 /* we don't always have a dentry for what we want to add, so people
1593  * like orphan dir can call this instead.
1594  *
1595  * The lookup context must have been filled from
1596  * ocfs2_prepare_dir_for_insert.
1597  */
1598 int __ocfs2_add_entry(handle_t *handle,
1599 		      struct inode *dir,
1600 		      const char *name, int namelen,
1601 		      struct inode *inode, u64 blkno,
1602 		      struct buffer_head *parent_fe_bh,
1603 		      struct ocfs2_dir_lookup_result *lookup)
1604 {
1605 	unsigned long offset;
1606 	unsigned short rec_len;
1607 	struct ocfs2_dir_entry *de, *de1;
1608 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_fe_bh->b_data;
1609 	struct super_block *sb = dir->i_sb;
1610 	int retval;
1611 	unsigned int size = sb->s_blocksize;
1612 	struct buffer_head *insert_bh = lookup->dl_leaf_bh;
1613 	char *data_start = insert_bh->b_data;
1614 
1615 	if (ocfs2_dir_indexed(dir)) {
1616 		struct buffer_head *bh;
1617 
1618 		/*
1619 		 * An indexed dir may require that we update the free space
1620 		 * list. Reserve a write to the previous node in the list so
1621 		 * that we don't fail later.
1622 		 *
1623 		 * XXX: This can be either a dx_root_block, or an unindexed
1624 		 * directory tree leaf block.
1625 		 */
1626 		if (ocfs2_free_list_at_root(lookup)) {
1627 			bh = lookup->dl_dx_root_bh;
1628 			retval = ocfs2_journal_access_dr(handle,
1629 						 INODE_CACHE(dir), bh,
1630 						 OCFS2_JOURNAL_ACCESS_WRITE);
1631 		} else {
1632 			bh = lookup->dl_prev_leaf_bh;
1633 			retval = ocfs2_journal_access_db(handle,
1634 						 INODE_CACHE(dir), bh,
1635 						 OCFS2_JOURNAL_ACCESS_WRITE);
1636 		}
1637 		if (retval) {
1638 			mlog_errno(retval);
1639 			return retval;
1640 		}
1641 	} else if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1642 		data_start = di->id2.i_data.id_data;
1643 		size = i_size_read(dir);
1644 
1645 		BUG_ON(insert_bh != parent_fe_bh);
1646 	}
1647 
1648 	rec_len = OCFS2_DIR_REC_LEN(namelen);
1649 	offset = 0;
1650 	de = (struct ocfs2_dir_entry *) data_start;
1651 	while (1) {
1652 		BUG_ON((char *)de >= (size + data_start));
1653 
1654 		/* These checks should've already been passed by the
1655 		 * prepare function, but I guess we can leave them
1656 		 * here anyway. */
1657 		if (!ocfs2_check_dir_entry(dir, de, insert_bh, data_start,
1658 					   size, offset)) {
1659 			retval = -ENOENT;
1660 			goto bail;
1661 		}
1662 		if (ocfs2_match(namelen, name, de)) {
1663 			retval = -EEXIST;
1664 			goto bail;
1665 		}
1666 
1667 		/* We're guaranteed that we should have space, so we
1668 		 * can't possibly have hit the trailer...right? */
1669 		mlog_bug_on_msg(ocfs2_skip_dir_trailer(dir, de, offset, size),
1670 				"Hit dir trailer trying to insert %.*s "
1671 			        "(namelen %d) into directory %llu.  "
1672 				"offset is %lu, trailer offset is %d\n",
1673 				namelen, name, namelen,
1674 				(unsigned long long)parent_fe_bh->b_blocknr,
1675 				offset, ocfs2_dir_trailer_blk_off(dir->i_sb));
1676 
1677 		if (ocfs2_dirent_would_fit(de, rec_len)) {
1678 			inode_set_mtime_to_ts(dir,
1679 					      inode_set_ctime_current(dir));
1680 			retval = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
1681 			if (retval < 0) {
1682 				mlog_errno(retval);
1683 				goto bail;
1684 			}
1685 
1686 			if (insert_bh == parent_fe_bh)
1687 				retval = ocfs2_journal_access_di(handle,
1688 								 INODE_CACHE(dir),
1689 								 insert_bh,
1690 								 OCFS2_JOURNAL_ACCESS_WRITE);
1691 			else {
1692 				retval = ocfs2_journal_access_db(handle,
1693 								 INODE_CACHE(dir),
1694 								 insert_bh,
1695 					      OCFS2_JOURNAL_ACCESS_WRITE);
1696 
1697 				if (!retval && ocfs2_dir_indexed(dir))
1698 					retval = ocfs2_dx_dir_insert(dir,
1699 								handle,
1700 								lookup);
1701 			}
1702 
1703 			if (retval) {
1704 				mlog_errno(retval);
1705 				goto bail;
1706 			}
1707 
1708 			/* By now the buffer is marked for journaling */
1709 			offset += le16_to_cpu(de->rec_len);
1710 			if (le64_to_cpu(de->inode)) {
1711 				de1 = (struct ocfs2_dir_entry *)((char *) de +
1712 					OCFS2_DIR_REC_LEN(de->name_len));
1713 				de1->rec_len =
1714 					cpu_to_le16(le16_to_cpu(de->rec_len) -
1715 					OCFS2_DIR_REC_LEN(de->name_len));
1716 				de->rec_len = cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
1717 				de = de1;
1718 			}
1719 			de->file_type = FT_UNKNOWN;
1720 			if (blkno) {
1721 				de->inode = cpu_to_le64(blkno);
1722 				ocfs2_set_de_type(de, inode->i_mode);
1723 			} else
1724 				de->inode = 0;
1725 			de->name_len = namelen;
1726 			memcpy(de->name, name, namelen);
1727 
1728 			if (ocfs2_dir_indexed(dir))
1729 				ocfs2_recalc_free_list(dir, handle, lookup);
1730 
1731 			inode_inc_iversion(dir);
1732 			ocfs2_journal_dirty(handle, insert_bh);
1733 			retval = 0;
1734 			goto bail;
1735 		}
1736 
1737 		offset += le16_to_cpu(de->rec_len);
1738 		de = (struct ocfs2_dir_entry *) ((char *) de + le16_to_cpu(de->rec_len));
1739 	}
1740 
1741 	/* when you think about it, the assert above should prevent us
1742 	 * from ever getting here. */
1743 	retval = -ENOSPC;
1744 bail:
1745 	if (retval)
1746 		mlog_errno(retval);
1747 
1748 	return retval;
1749 }
1750 
1751 static int ocfs2_dir_foreach_blk_id(struct inode *inode,
1752 				    u64 *f_version,
1753 				    struct dir_context *ctx)
1754 {
1755 	int ret, i;
1756 	unsigned long offset = ctx->pos;
1757 	struct buffer_head *di_bh = NULL;
1758 	struct ocfs2_dinode *di;
1759 	struct ocfs2_inline_data *data;
1760 	struct ocfs2_dir_entry *de;
1761 
1762 	ret = ocfs2_read_inode_block(inode, &di_bh);
1763 	if (ret) {
1764 		mlog(ML_ERROR, "Unable to read inode block for dir %llu\n",
1765 		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
1766 		goto out;
1767 	}
1768 
1769 	di = (struct ocfs2_dinode *)di_bh->b_data;
1770 	data = &di->id2.i_data;
1771 
1772 	while (ctx->pos < i_size_read(inode)) {
1773 		/* If the dir block has changed since the last call to
1774 		 * readdir(2), then we might be pointing to an invalid
1775 		 * dirent right now.  Scan from the start of the block
1776 		 * to make sure. */
1777 		if (!inode_eq_iversion(inode, *f_version)) {
1778 			for (i = 0; i < i_size_read(inode) && i < offset; ) {
1779 				de = (struct ocfs2_dir_entry *)
1780 					(data->id_data + i);
1781 				/* It's too expensive to do a full
1782 				 * dirent test each time round this
1783 				 * loop, but we do have to test at
1784 				 * least that it is non-zero.  A
1785 				 * failure will be detected in the
1786 				 * dirent test below. */
1787 				if (le16_to_cpu(de->rec_len) <
1788 				    OCFS2_DIR_REC_LEN(1))
1789 					break;
1790 				i += le16_to_cpu(de->rec_len);
1791 			}
1792 			ctx->pos = offset = i;
1793 			*f_version = inode_query_iversion(inode);
1794 		}
1795 
1796 		de = (struct ocfs2_dir_entry *) (data->id_data + ctx->pos);
1797 		if (!ocfs2_check_dir_entry(inode, de, di_bh, (char *)data->id_data,
1798 					   i_size_read(inode), ctx->pos)) {
1799 			/* On error, skip the f_pos to the end. */
1800 			ctx->pos = i_size_read(inode);
1801 			break;
1802 		}
1803 		offset += le16_to_cpu(de->rec_len);
1804 		if (le64_to_cpu(de->inode)) {
1805 			if (!dir_emit(ctx, de->name, de->name_len,
1806 				      le64_to_cpu(de->inode),
1807 				      fs_ftype_to_dtype(de->file_type)))
1808 				goto out;
1809 		}
1810 		ctx->pos += le16_to_cpu(de->rec_len);
1811 	}
1812 out:
1813 	brelse(di_bh);
1814 	return 0;
1815 }
1816 
1817 /*
1818  * NOTE: This function can be called against unindexed directories,
1819  * and indexed ones.
1820  */
1821 static int ocfs2_dir_foreach_blk_el(struct inode *inode,
1822 				    u64 *f_version,
1823 				    struct dir_context *ctx,
1824 				    bool persist)
1825 {
1826 	unsigned long offset, blk, last_ra_blk = 0;
1827 	int i;
1828 	struct buffer_head * bh, * tmp;
1829 	struct ocfs2_dir_entry * de;
1830 	struct super_block * sb = inode->i_sb;
1831 	unsigned int ra_sectors = 16;
1832 	int stored = 0;
1833 
1834 	bh = NULL;
1835 
1836 	offset = ctx->pos & (sb->s_blocksize - 1);
1837 
1838 	while (ctx->pos < i_size_read(inode)) {
1839 		blk = ctx->pos >> sb->s_blocksize_bits;
1840 		if (ocfs2_read_dir_block(inode, blk, &bh, 0)) {
1841 			/* Skip the corrupt dirblock and keep trying */
1842 			ctx->pos += sb->s_blocksize - offset;
1843 			continue;
1844 		}
1845 
1846 		/* The idea here is to begin with 8k read-ahead and to stay
1847 		 * 4k ahead of our current position.
1848 		 *
1849 		 * TODO: Use the pagecache for this. We just need to
1850 		 * make sure it's cluster-safe... */
1851 		if (!last_ra_blk
1852 		    || (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) {
1853 			for (i = ra_sectors >> (sb->s_blocksize_bits - 9);
1854 			     i > 0; i--) {
1855 				tmp = NULL;
1856 				if (!ocfs2_read_dir_block(inode, ++blk, &tmp,
1857 							  OCFS2_BH_READAHEAD))
1858 					brelse(tmp);
1859 			}
1860 			last_ra_blk = blk;
1861 			ra_sectors = 8;
1862 		}
1863 
1864 		/* If the dir block has changed since the last call to
1865 		 * readdir(2), then we might be pointing to an invalid
1866 		 * dirent right now.  Scan from the start of the block
1867 		 * to make sure. */
1868 		if (!inode_eq_iversion(inode, *f_version)) {
1869 			for (i = 0; i < sb->s_blocksize && i < offset; ) {
1870 				de = (struct ocfs2_dir_entry *) (bh->b_data + i);
1871 				/* It's too expensive to do a full
1872 				 * dirent test each time round this
1873 				 * loop, but we do have to test at
1874 				 * least that it is non-zero.  A
1875 				 * failure will be detected in the
1876 				 * dirent test below. */
1877 				if (le16_to_cpu(de->rec_len) <
1878 				    OCFS2_DIR_REC_LEN(1))
1879 					break;
1880 				i += le16_to_cpu(de->rec_len);
1881 			}
1882 			offset = i;
1883 			ctx->pos = (ctx->pos & ~(sb->s_blocksize - 1))
1884 				| offset;
1885 			*f_version = inode_query_iversion(inode);
1886 		}
1887 
1888 		while (ctx->pos < i_size_read(inode)
1889 		       && offset < sb->s_blocksize) {
1890 			de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
1891 			if (!ocfs2_check_dir_entry(inode, de, bh, bh->b_data,
1892 						   sb->s_blocksize, offset)) {
1893 				/* On error, skip the f_pos to the
1894 				   next block. */
1895 				ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
1896 				break;
1897 			}
1898 			if (le64_to_cpu(de->inode)) {
1899 				if (!dir_emit(ctx, de->name,
1900 						de->name_len,
1901 						le64_to_cpu(de->inode),
1902 					fs_ftype_to_dtype(de->file_type))) {
1903 					brelse(bh);
1904 					return 0;
1905 				}
1906 				stored++;
1907 			}
1908 			offset += le16_to_cpu(de->rec_len);
1909 			ctx->pos += le16_to_cpu(de->rec_len);
1910 		}
1911 		offset = 0;
1912 		brelse(bh);
1913 		bh = NULL;
1914 		if (!persist && stored)
1915 			break;
1916 	}
1917 	return 0;
1918 }
1919 
1920 static int ocfs2_dir_foreach_blk(struct inode *inode, u64 *f_version,
1921 				 struct dir_context *ctx,
1922 				 bool persist)
1923 {
1924 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1925 		return ocfs2_dir_foreach_blk_id(inode, f_version, ctx);
1926 	return ocfs2_dir_foreach_blk_el(inode, f_version, ctx, persist);
1927 }
1928 
1929 /*
1930  * This is intended to be called from inside other kernel functions,
1931  * so we fake some arguments.
1932  */
1933 int ocfs2_dir_foreach(struct inode *inode, struct dir_context *ctx)
1934 {
1935 	u64 version = inode_query_iversion(inode);
1936 	ocfs2_dir_foreach_blk(inode, &version, ctx, true);
1937 	return 0;
1938 }
1939 
1940 /*
1941  * ocfs2_readdir()
1942  *
1943  */
1944 int ocfs2_readdir(struct file *file, struct dir_context *ctx)
1945 {
1946 	int error = 0;
1947 	struct inode *inode = file_inode(file);
1948 	struct ocfs2_file_private *fp = file->private_data;
1949 	int lock_level = 0;
1950 
1951 	trace_ocfs2_readdir((unsigned long long)OCFS2_I(inode)->ip_blkno);
1952 
1953 	error = ocfs2_inode_lock_atime(inode, file->f_path.mnt, &lock_level, 1);
1954 	if (lock_level && error >= 0) {
1955 		/* We release EX lock which used to update atime
1956 		 * and get PR lock again to reduce contention
1957 		 * on commonly accessed directories. */
1958 		ocfs2_inode_unlock(inode, 1);
1959 		lock_level = 0;
1960 		error = ocfs2_inode_lock(inode, NULL, 0);
1961 	}
1962 	if (error < 0) {
1963 		if (error != -ENOENT)
1964 			mlog_errno(error);
1965 		/* we haven't got any yet, so propagate the error. */
1966 		goto bail_nolock;
1967 	}
1968 
1969 	error = ocfs2_dir_foreach_blk(inode, &fp->cookie, ctx, false);
1970 
1971 	ocfs2_inode_unlock(inode, lock_level);
1972 	if (error)
1973 		mlog_errno(error);
1974 
1975 bail_nolock:
1976 
1977 	return error;
1978 }
1979 
1980 /*
1981  * NOTE: this should always be called with parent dir i_rwsem taken.
1982  */
1983 int ocfs2_find_files_on_disk(const char *name,
1984 			     int namelen,
1985 			     u64 *blkno,
1986 			     struct inode *inode,
1987 			     struct ocfs2_dir_lookup_result *lookup)
1988 {
1989 	int status = -ENOENT;
1990 
1991 	trace_ocfs2_find_files_on_disk(namelen, name, blkno,
1992 				(unsigned long long)OCFS2_I(inode)->ip_blkno);
1993 
1994 	status = ocfs2_find_entry(name, namelen, inode, lookup);
1995 	if (status)
1996 		goto leave;
1997 
1998 	*blkno = le64_to_cpu(lookup->dl_entry->inode);
1999 
2000 	status = 0;
2001 leave:
2002 
2003 	return status;
2004 }
2005 
2006 /*
2007  * Convenience function for callers which just want the block number
2008  * mapped to a name and don't require the full dirent info, etc.
2009  */
2010 int ocfs2_lookup_ino_from_name(struct inode *dir, const char *name,
2011 			       int namelen, u64 *blkno)
2012 {
2013 	int ret;
2014 	struct ocfs2_dir_lookup_result lookup = { NULL, };
2015 
2016 	ret = ocfs2_find_files_on_disk(name, namelen, blkno, dir, &lookup);
2017 	ocfs2_free_dir_lookup_result(&lookup);
2018 
2019 	return ret;
2020 }
2021 
2022 /* Check for a name within a directory.
2023  *
2024  * Return 0 if the name does not exist
2025  * Return -EEXIST if the directory contains the name
2026  * Return -EFSCORRUPTED if found corruption
2027  *
2028  * Callers should have i_rwsem + a cluster lock on dir
2029  */
2030 int ocfs2_check_dir_for_entry(struct inode *dir,
2031 			      const char *name,
2032 			      int namelen)
2033 {
2034 	int ret = 0;
2035 	struct ocfs2_dir_lookup_result lookup = { NULL, };
2036 
2037 	trace_ocfs2_check_dir_for_entry(
2038 		(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
2039 
2040 	ret = ocfs2_find_entry(name, namelen, dir, &lookup);
2041 	if (ret == 0) {
2042 		ret = -EEXIST;
2043 		mlog_errno(ret);
2044 	} else if (ret == -ENOENT) {
2045 		ret = 0;
2046 	}
2047 
2048 	ocfs2_free_dir_lookup_result(&lookup);
2049 
2050 	return ret;
2051 }
2052 
2053 struct ocfs2_empty_dir_priv {
2054 	struct dir_context ctx;
2055 	unsigned seen_dot;
2056 	unsigned seen_dot_dot;
2057 	unsigned seen_other;
2058 	unsigned dx_dir;
2059 };
2060 static bool ocfs2_empty_dir_filldir(struct dir_context *ctx, const char *name,
2061 				   int name_len, loff_t pos, u64 ino,
2062 				   unsigned type)
2063 {
2064 	struct ocfs2_empty_dir_priv *p =
2065 		container_of(ctx, struct ocfs2_empty_dir_priv, ctx);
2066 
2067 	/*
2068 	 * Check the positions of "." and ".." records to be sure
2069 	 * they're in the correct place.
2070 	 *
2071 	 * Indexed directories don't need to proceed past the first
2072 	 * two entries, so we end the scan after seeing '..'. Despite
2073 	 * that, we allow the scan to proceed In the event that we
2074 	 * have a corrupted indexed directory (no dot or dot dot
2075 	 * entries). This allows us to double check for existing
2076 	 * entries which might not have been found in the index.
2077 	 */
2078 	if (name_len == 1 && !strncmp(".", name, 1) && pos == 0) {
2079 		p->seen_dot = 1;
2080 		return true;
2081 	}
2082 
2083 	if (name_len == 2 && !strncmp("..", name, 2) &&
2084 	    pos == OCFS2_DIR_REC_LEN(1)) {
2085 		p->seen_dot_dot = 1;
2086 
2087 		if (p->dx_dir && p->seen_dot)
2088 			return false;
2089 
2090 		return true;
2091 	}
2092 
2093 	p->seen_other = 1;
2094 	return false;
2095 }
2096 
2097 static int ocfs2_empty_dir_dx(struct inode *inode,
2098 			      struct ocfs2_empty_dir_priv *priv)
2099 {
2100 	int ret;
2101 	struct buffer_head *di_bh = NULL;
2102 	struct buffer_head *dx_root_bh = NULL;
2103 	struct ocfs2_dinode *di;
2104 	struct ocfs2_dx_root_block *dx_root;
2105 
2106 	priv->dx_dir = 1;
2107 
2108 	ret = ocfs2_read_inode_block(inode, &di_bh);
2109 	if (ret) {
2110 		mlog_errno(ret);
2111 		goto out;
2112 	}
2113 	di = (struct ocfs2_dinode *)di_bh->b_data;
2114 
2115 	ret = ocfs2_read_dx_root(inode, di, &dx_root_bh);
2116 	if (ret) {
2117 		mlog_errno(ret);
2118 		goto out;
2119 	}
2120 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2121 
2122 	if (le32_to_cpu(dx_root->dr_num_entries) != 2)
2123 		priv->seen_other = 1;
2124 
2125 out:
2126 	brelse(di_bh);
2127 	brelse(dx_root_bh);
2128 	return ret;
2129 }
2130 
2131 /*
2132  * routine to check that the specified directory is empty (for rmdir)
2133  *
2134  * Returns 1 if dir is empty, zero otherwise.
2135  *
2136  * XXX: This is a performance problem for unindexed directories.
2137  */
2138 int ocfs2_empty_dir(struct inode *inode)
2139 {
2140 	int ret;
2141 	struct ocfs2_empty_dir_priv priv = {
2142 		.ctx.actor = ocfs2_empty_dir_filldir,
2143 	};
2144 
2145 	if (ocfs2_dir_indexed(inode)) {
2146 		ret = ocfs2_empty_dir_dx(inode, &priv);
2147 		if (ret)
2148 			mlog_errno(ret);
2149 		/*
2150 		 * We still run ocfs2_dir_foreach to get the checks
2151 		 * for "." and "..".
2152 		 */
2153 	}
2154 
2155 	ret = ocfs2_dir_foreach(inode, &priv.ctx);
2156 	if (ret)
2157 		mlog_errno(ret);
2158 
2159 	if (!priv.seen_dot || !priv.seen_dot_dot) {
2160 		mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
2161 		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
2162 		/*
2163 		 * XXX: Is it really safe to allow an unlink to continue?
2164 		 */
2165 		return 1;
2166 	}
2167 
2168 	return !priv.seen_other;
2169 }
2170 
2171 /*
2172  * Fills "." and ".." dirents in a new directory block. Returns dirent for
2173  * "..", which might be used during creation of a directory with a trailing
2174  * header. It is otherwise safe to ignore the return code.
2175  */
2176 static struct ocfs2_dir_entry *ocfs2_fill_initial_dirents(struct inode *inode,
2177 							  struct inode *parent,
2178 							  char *start,
2179 							  unsigned int size)
2180 {
2181 	struct ocfs2_dir_entry *de = (struct ocfs2_dir_entry *)start;
2182 
2183 	de->inode = cpu_to_le64(OCFS2_I(inode)->ip_blkno);
2184 	de->name_len = 1;
2185 	de->rec_len =
2186 		cpu_to_le16(OCFS2_DIR_REC_LEN(de->name_len));
2187 	strcpy(de->name, ".");
2188 	ocfs2_set_de_type(de, S_IFDIR);
2189 
2190 	de = (struct ocfs2_dir_entry *) ((char *)de + le16_to_cpu(de->rec_len));
2191 	de->inode = cpu_to_le64(OCFS2_I(parent)->ip_blkno);
2192 	de->rec_len = cpu_to_le16(size - OCFS2_DIR_REC_LEN(1));
2193 	de->name_len = 2;
2194 	strcpy(de->name, "..");
2195 	ocfs2_set_de_type(de, S_IFDIR);
2196 
2197 	return de;
2198 }
2199 
2200 /*
2201  * This works together with code in ocfs2_mknod_locked() which sets
2202  * the inline-data flag and initializes the inline-data section.
2203  */
2204 static int ocfs2_fill_new_dir_id(struct ocfs2_super *osb,
2205 				 handle_t *handle,
2206 				 struct inode *parent,
2207 				 struct inode *inode,
2208 				 struct buffer_head *di_bh)
2209 {
2210 	int ret;
2211 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
2212 	struct ocfs2_inline_data *data = &di->id2.i_data;
2213 	unsigned int size = le16_to_cpu(data->id_count);
2214 
2215 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
2216 				      OCFS2_JOURNAL_ACCESS_WRITE);
2217 	if (ret) {
2218 		mlog_errno(ret);
2219 		goto out;
2220 	}
2221 
2222 	ocfs2_fill_initial_dirents(inode, parent, data->id_data, size);
2223 	ocfs2_journal_dirty(handle, di_bh);
2224 
2225 	i_size_write(inode, size);
2226 	set_nlink(inode, 2);
2227 	inode->i_blocks = ocfs2_inode_sector_count(inode);
2228 
2229 	ret = ocfs2_mark_inode_dirty(handle, inode, di_bh);
2230 	if (ret < 0)
2231 		mlog_errno(ret);
2232 
2233 out:
2234 	return ret;
2235 }
2236 
2237 static int ocfs2_fill_new_dir_el(struct ocfs2_super *osb,
2238 				 handle_t *handle,
2239 				 struct inode *parent,
2240 				 struct inode *inode,
2241 				 struct buffer_head *fe_bh,
2242 				 struct ocfs2_alloc_context *data_ac,
2243 				 struct buffer_head **ret_new_bh)
2244 {
2245 	int status;
2246 	unsigned int size = osb->sb->s_blocksize;
2247 	struct buffer_head *new_bh = NULL;
2248 	struct ocfs2_dir_entry *de;
2249 
2250 	if (ocfs2_new_dir_wants_trailer(inode))
2251 		size = ocfs2_dir_trailer_blk_off(parent->i_sb);
2252 
2253 	status = ocfs2_do_extend_dir(osb->sb, handle, inode, fe_bh,
2254 				     data_ac, NULL, &new_bh);
2255 	if (status < 0) {
2256 		mlog_errno(status);
2257 		goto bail;
2258 	}
2259 
2260 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), new_bh);
2261 
2262 	status = ocfs2_journal_access_db(handle, INODE_CACHE(inode), new_bh,
2263 					 OCFS2_JOURNAL_ACCESS_CREATE);
2264 	if (status < 0) {
2265 		mlog_errno(status);
2266 		goto bail;
2267 	}
2268 	memset(new_bh->b_data, 0, osb->sb->s_blocksize);
2269 
2270 	de = ocfs2_fill_initial_dirents(inode, parent, new_bh->b_data, size);
2271 	if (ocfs2_new_dir_wants_trailer(inode)) {
2272 		int size = le16_to_cpu(de->rec_len);
2273 
2274 		/*
2275 		 * Figure out the size of the hole left over after
2276 		 * insertion of '.' and '..'. The trailer wants this
2277 		 * information.
2278 		 */
2279 		size -= OCFS2_DIR_REC_LEN(2);
2280 		size -= sizeof(struct ocfs2_dir_block_trailer);
2281 
2282 		ocfs2_init_dir_trailer(inode, new_bh, size);
2283 	}
2284 
2285 	ocfs2_journal_dirty(handle, new_bh);
2286 
2287 	i_size_write(inode, inode->i_sb->s_blocksize);
2288 	set_nlink(inode, 2);
2289 	inode->i_blocks = ocfs2_inode_sector_count(inode);
2290 	status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
2291 	if (status < 0) {
2292 		mlog_errno(status);
2293 		goto bail;
2294 	}
2295 
2296 	status = 0;
2297 	if (ret_new_bh) {
2298 		*ret_new_bh = new_bh;
2299 		new_bh = NULL;
2300 	}
2301 bail:
2302 	brelse(new_bh);
2303 
2304 	return status;
2305 }
2306 
2307 static int ocfs2_dx_dir_attach_index(struct ocfs2_super *osb,
2308 				     handle_t *handle, struct inode *dir,
2309 				     struct buffer_head *di_bh,
2310 				     struct buffer_head *dirdata_bh,
2311 				     struct ocfs2_alloc_context *meta_ac,
2312 				     int dx_inline, u32 num_entries,
2313 				     struct buffer_head **ret_dx_root_bh)
2314 {
2315 	int ret;
2316 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
2317 	u16 dr_suballoc_bit;
2318 	u64 suballoc_loc, dr_blkno;
2319 	unsigned int num_bits;
2320 	struct buffer_head *dx_root_bh = NULL;
2321 	struct ocfs2_dx_root_block *dx_root;
2322 	struct ocfs2_dir_block_trailer *trailer =
2323 		ocfs2_trailer_from_bh(dirdata_bh, dir->i_sb);
2324 
2325 	ret = ocfs2_claim_metadata(handle, meta_ac, 1, &suballoc_loc,
2326 				   &dr_suballoc_bit, &num_bits, &dr_blkno);
2327 	if (ret) {
2328 		mlog_errno(ret);
2329 		goto out;
2330 	}
2331 
2332 	trace_ocfs2_dx_dir_attach_index(
2333 				(unsigned long long)OCFS2_I(dir)->ip_blkno,
2334 				(unsigned long long)dr_blkno);
2335 
2336 	dx_root_bh = sb_getblk(osb->sb, dr_blkno);
2337 	if (dx_root_bh == NULL) {
2338 		ret = -ENOMEM;
2339 		goto out;
2340 	}
2341 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), dx_root_bh);
2342 
2343 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
2344 				      OCFS2_JOURNAL_ACCESS_CREATE);
2345 	if (ret < 0) {
2346 		mlog_errno(ret);
2347 		goto out;
2348 	}
2349 
2350 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2351 	memset(dx_root, 0, osb->sb->s_blocksize);
2352 	strcpy(dx_root->dr_signature, OCFS2_DX_ROOT_SIGNATURE);
2353 	dx_root->dr_suballoc_slot = cpu_to_le16(meta_ac->ac_alloc_slot);
2354 	dx_root->dr_suballoc_loc = cpu_to_le64(suballoc_loc);
2355 	dx_root->dr_suballoc_bit = cpu_to_le16(dr_suballoc_bit);
2356 	dx_root->dr_fs_generation = cpu_to_le32(osb->fs_generation);
2357 	dx_root->dr_blkno = cpu_to_le64(dr_blkno);
2358 	dx_root->dr_dir_blkno = cpu_to_le64(OCFS2_I(dir)->ip_blkno);
2359 	dx_root->dr_num_entries = cpu_to_le32(num_entries);
2360 	if (le16_to_cpu(trailer->db_free_rec_len))
2361 		dx_root->dr_free_blk = cpu_to_le64(dirdata_bh->b_blocknr);
2362 	else
2363 		dx_root->dr_free_blk = cpu_to_le64(0);
2364 
2365 	if (dx_inline) {
2366 		dx_root->dr_flags |= OCFS2_DX_FLAG_INLINE;
2367 		dx_root->dr_entries.de_count =
2368 			cpu_to_le16(ocfs2_dx_entries_per_root(osb->sb));
2369 	} else {
2370 		dx_root->dr_list.l_count =
2371 			cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
2372 	}
2373 	ocfs2_journal_dirty(handle, dx_root_bh);
2374 
2375 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
2376 				      OCFS2_JOURNAL_ACCESS_CREATE);
2377 	if (ret) {
2378 		mlog_errno(ret);
2379 		goto out;
2380 	}
2381 
2382 	di->i_dx_root = cpu_to_le64(dr_blkno);
2383 
2384 	spin_lock(&OCFS2_I(dir)->ip_lock);
2385 	OCFS2_I(dir)->ip_dyn_features |= OCFS2_INDEXED_DIR_FL;
2386 	di->i_dyn_features = cpu_to_le16(OCFS2_I(dir)->ip_dyn_features);
2387 	spin_unlock(&OCFS2_I(dir)->ip_lock);
2388 
2389 	ocfs2_journal_dirty(handle, di_bh);
2390 
2391 	*ret_dx_root_bh = dx_root_bh;
2392 	dx_root_bh = NULL;
2393 
2394 out:
2395 	brelse(dx_root_bh);
2396 	return ret;
2397 }
2398 
2399 static int ocfs2_dx_dir_format_cluster(struct ocfs2_super *osb,
2400 				       handle_t *handle, struct inode *dir,
2401 				       struct buffer_head **dx_leaves,
2402 				       int num_dx_leaves, u64 start_blk)
2403 {
2404 	int ret, i;
2405 	struct ocfs2_dx_leaf *dx_leaf;
2406 	struct buffer_head *bh;
2407 
2408 	for (i = 0; i < num_dx_leaves; i++) {
2409 		bh = sb_getblk(osb->sb, start_blk + i);
2410 		if (bh == NULL) {
2411 			ret = -ENOMEM;
2412 			goto out;
2413 		}
2414 		dx_leaves[i] = bh;
2415 
2416 		ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), bh);
2417 
2418 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), bh,
2419 					      OCFS2_JOURNAL_ACCESS_CREATE);
2420 		if (ret < 0) {
2421 			mlog_errno(ret);
2422 			goto out;
2423 		}
2424 
2425 		dx_leaf = (struct ocfs2_dx_leaf *) bh->b_data;
2426 
2427 		memset(dx_leaf, 0, osb->sb->s_blocksize);
2428 		strcpy(dx_leaf->dl_signature, OCFS2_DX_LEAF_SIGNATURE);
2429 		dx_leaf->dl_fs_generation = cpu_to_le32(osb->fs_generation);
2430 		dx_leaf->dl_blkno = cpu_to_le64(bh->b_blocknr);
2431 		dx_leaf->dl_list.de_count =
2432 			cpu_to_le16(ocfs2_dx_entries_per_leaf(osb->sb));
2433 
2434 		trace_ocfs2_dx_dir_format_cluster(
2435 				(unsigned long long)OCFS2_I(dir)->ip_blkno,
2436 				(unsigned long long)bh->b_blocknr,
2437 				le16_to_cpu(dx_leaf->dl_list.de_count));
2438 
2439 		ocfs2_journal_dirty(handle, bh);
2440 	}
2441 
2442 	ret = 0;
2443 out:
2444 	return ret;
2445 }
2446 
2447 /*
2448  * Allocates and formats a new cluster for use in an indexed dir
2449  * leaf. This version will not do the extent insert, so that it can be
2450  * used by operations which need careful ordering.
2451  */
2452 static int __ocfs2_dx_dir_new_cluster(struct inode *dir,
2453 				      u32 cpos, handle_t *handle,
2454 				      struct ocfs2_alloc_context *data_ac,
2455 				      struct buffer_head **dx_leaves,
2456 				      int num_dx_leaves, u64 *ret_phys_blkno)
2457 {
2458 	int ret;
2459 	u32 phys, num;
2460 	u64 phys_blkno;
2461 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
2462 
2463 	/*
2464 	 * XXX: For create, this should claim cluster for the index
2465 	 * *before* the unindexed insert so that we have a better
2466 	 * chance of contiguousness as the directory grows in number
2467 	 * of entries.
2468 	 */
2469 	ret = __ocfs2_claim_clusters(handle, data_ac, 1, 1, &phys, &num);
2470 	if (ret) {
2471 		mlog_errno(ret);
2472 		goto out;
2473 	}
2474 
2475 	/*
2476 	 * Format the new cluster first. That way, we're inserting
2477 	 * valid data.
2478 	 */
2479 	phys_blkno = ocfs2_clusters_to_blocks(osb->sb, phys);
2480 	ret = ocfs2_dx_dir_format_cluster(osb, handle, dir, dx_leaves,
2481 					  num_dx_leaves, phys_blkno);
2482 	if (ret) {
2483 		mlog_errno(ret);
2484 		goto out;
2485 	}
2486 
2487 	*ret_phys_blkno = phys_blkno;
2488 out:
2489 	return ret;
2490 }
2491 
2492 static int ocfs2_dx_dir_new_cluster(struct inode *dir,
2493 				    struct ocfs2_extent_tree *et,
2494 				    u32 cpos, handle_t *handle,
2495 				    struct ocfs2_alloc_context *data_ac,
2496 				    struct ocfs2_alloc_context *meta_ac,
2497 				    struct buffer_head **dx_leaves,
2498 				    int num_dx_leaves)
2499 {
2500 	int ret;
2501 	u64 phys_blkno;
2502 
2503 	ret = __ocfs2_dx_dir_new_cluster(dir, cpos, handle, data_ac, dx_leaves,
2504 					 num_dx_leaves, &phys_blkno);
2505 	if (ret) {
2506 		mlog_errno(ret);
2507 		goto out;
2508 	}
2509 
2510 	ret = ocfs2_insert_extent(handle, et, cpos, phys_blkno, 1, 0,
2511 				  meta_ac);
2512 	if (ret)
2513 		mlog_errno(ret);
2514 out:
2515 	return ret;
2516 }
2517 
2518 static struct buffer_head **ocfs2_dx_dir_kmalloc_leaves(struct super_block *sb,
2519 							int *ret_num_leaves)
2520 {
2521 	int num_dx_leaves = ocfs2_clusters_to_blocks(sb, 1);
2522 	struct buffer_head **dx_leaves;
2523 
2524 	dx_leaves = kcalloc(num_dx_leaves, sizeof(struct buffer_head *),
2525 			    GFP_NOFS);
2526 	if (dx_leaves && ret_num_leaves)
2527 		*ret_num_leaves = num_dx_leaves;
2528 
2529 	return dx_leaves;
2530 }
2531 
2532 static int ocfs2_fill_new_dir_dx(struct ocfs2_super *osb,
2533 				 handle_t *handle,
2534 				 struct inode *parent,
2535 				 struct inode *inode,
2536 				 struct buffer_head *di_bh,
2537 				 struct ocfs2_alloc_context *data_ac,
2538 				 struct ocfs2_alloc_context *meta_ac)
2539 {
2540 	int ret;
2541 	struct buffer_head *leaf_bh = NULL;
2542 	struct buffer_head *dx_root_bh = NULL;
2543 	struct ocfs2_dx_hinfo hinfo;
2544 	struct ocfs2_dx_root_block *dx_root;
2545 	struct ocfs2_dx_entry_list *entry_list;
2546 
2547 	/*
2548 	 * Our strategy is to create the directory as though it were
2549 	 * unindexed, then add the index block. This works with very
2550 	 * little complication since the state of a new directory is a
2551 	 * very well known quantity.
2552 	 *
2553 	 * Essentially, we have two dirents ("." and ".."), in the 1st
2554 	 * block which need indexing. These are easily inserted into
2555 	 * the index block.
2556 	 */
2557 
2558 	ret = ocfs2_fill_new_dir_el(osb, handle, parent, inode, di_bh,
2559 				    data_ac, &leaf_bh);
2560 	if (ret) {
2561 		mlog_errno(ret);
2562 		goto out;
2563 	}
2564 
2565 	ret = ocfs2_dx_dir_attach_index(osb, handle, inode, di_bh, leaf_bh,
2566 					meta_ac, 1, 2, &dx_root_bh);
2567 	if (ret) {
2568 		mlog_errno(ret);
2569 		goto out;
2570 	}
2571 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2572 	entry_list = &dx_root->dr_entries;
2573 
2574 	/* Buffer has been journaled for us by ocfs2_dx_dir_attach_index */
2575 	ocfs2_dx_dir_name_hash(inode, ".", 1, &hinfo);
2576 	ocfs2_dx_entry_list_insert(entry_list, &hinfo, leaf_bh->b_blocknr);
2577 
2578 	ocfs2_dx_dir_name_hash(inode, "..", 2, &hinfo);
2579 	ocfs2_dx_entry_list_insert(entry_list, &hinfo, leaf_bh->b_blocknr);
2580 
2581 out:
2582 	brelse(dx_root_bh);
2583 	brelse(leaf_bh);
2584 	return ret;
2585 }
2586 
2587 int ocfs2_fill_new_dir(struct ocfs2_super *osb,
2588 		       handle_t *handle,
2589 		       struct inode *parent,
2590 		       struct inode *inode,
2591 		       struct buffer_head *fe_bh,
2592 		       struct ocfs2_alloc_context *data_ac,
2593 		       struct ocfs2_alloc_context *meta_ac)
2594 
2595 {
2596 	BUG_ON(!ocfs2_supports_inline_data(osb) && data_ac == NULL);
2597 
2598 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
2599 		return ocfs2_fill_new_dir_id(osb, handle, parent, inode, fe_bh);
2600 
2601 	if (ocfs2_supports_indexed_dirs(osb))
2602 		return ocfs2_fill_new_dir_dx(osb, handle, parent, inode, fe_bh,
2603 					     data_ac, meta_ac);
2604 
2605 	return ocfs2_fill_new_dir_el(osb, handle, parent, inode, fe_bh,
2606 				     data_ac, NULL);
2607 }
2608 
2609 static int ocfs2_dx_dir_index_block(struct inode *dir,
2610 				    handle_t *handle,
2611 				    struct buffer_head **dx_leaves,
2612 				    int num_dx_leaves,
2613 				    u32 *num_dx_entries,
2614 				    struct buffer_head *dirent_bh)
2615 {
2616 	int ret = 0, namelen, i;
2617 	char *de_buf, *limit;
2618 	struct ocfs2_dir_entry *de;
2619 	struct buffer_head *dx_leaf_bh;
2620 	struct ocfs2_dx_hinfo hinfo;
2621 	u64 dirent_blk = dirent_bh->b_blocknr;
2622 
2623 	de_buf = dirent_bh->b_data;
2624 	limit = de_buf + dir->i_sb->s_blocksize;
2625 
2626 	while (de_buf < limit) {
2627 		de = (struct ocfs2_dir_entry *)de_buf;
2628 
2629 		namelen = de->name_len;
2630 		if (!namelen || !de->inode)
2631 			goto inc;
2632 
2633 		ocfs2_dx_dir_name_hash(dir, de->name, namelen, &hinfo);
2634 
2635 		i = ocfs2_dx_dir_hash_idx(OCFS2_SB(dir->i_sb), &hinfo);
2636 		dx_leaf_bh = dx_leaves[i];
2637 
2638 		ret = __ocfs2_dx_dir_leaf_insert(dir, handle, &hinfo,
2639 						 dirent_blk, dx_leaf_bh);
2640 		if (ret) {
2641 			mlog_errno(ret);
2642 			goto out;
2643 		}
2644 
2645 		*num_dx_entries = *num_dx_entries + 1;
2646 
2647 inc:
2648 		de_buf += le16_to_cpu(de->rec_len);
2649 	}
2650 
2651 out:
2652 	return ret;
2653 }
2654 
2655 /*
2656  * XXX: This expects dx_root_bh to already be part of the transaction.
2657  */
2658 static void ocfs2_dx_dir_index_root_block(struct inode *dir,
2659 					 struct buffer_head *dx_root_bh,
2660 					 struct buffer_head *dirent_bh)
2661 {
2662 	char *de_buf, *limit;
2663 	struct ocfs2_dx_root_block *dx_root;
2664 	struct ocfs2_dir_entry *de;
2665 	struct ocfs2_dx_hinfo hinfo;
2666 	u64 dirent_blk = dirent_bh->b_blocknr;
2667 
2668 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
2669 
2670 	de_buf = dirent_bh->b_data;
2671 	limit = de_buf + dir->i_sb->s_blocksize;
2672 
2673 	while (de_buf < limit) {
2674 		de = (struct ocfs2_dir_entry *)de_buf;
2675 
2676 		if (!de->name_len || !de->inode)
2677 			goto inc;
2678 
2679 		ocfs2_dx_dir_name_hash(dir, de->name, de->name_len, &hinfo);
2680 
2681 		trace_ocfs2_dx_dir_index_root_block(
2682 				(unsigned long long)dir->i_ino,
2683 				hinfo.major_hash, hinfo.minor_hash,
2684 				de->name_len, de->name,
2685 				le16_to_cpu(dx_root->dr_entries.de_num_used));
2686 
2687 		ocfs2_dx_entry_list_insert(&dx_root->dr_entries, &hinfo,
2688 					   dirent_blk);
2689 
2690 		le32_add_cpu(&dx_root->dr_num_entries, 1);
2691 inc:
2692 		de_buf += le16_to_cpu(de->rec_len);
2693 	}
2694 }
2695 
2696 /*
2697  * Count the number of inline directory entries in di_bh and compare
2698  * them against the number of entries we can hold in an inline dx root
2699  * block.
2700  */
2701 static int ocfs2_new_dx_should_be_inline(struct inode *dir,
2702 					 struct buffer_head *di_bh)
2703 {
2704 	int dirent_count = 0;
2705 	char *de_buf, *limit;
2706 	struct ocfs2_dir_entry *de;
2707 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
2708 
2709 	de_buf = di->id2.i_data.id_data;
2710 	limit = de_buf + i_size_read(dir);
2711 
2712 	while (de_buf < limit) {
2713 		de = (struct ocfs2_dir_entry *)de_buf;
2714 
2715 		if (de->name_len && de->inode)
2716 			dirent_count++;
2717 
2718 		de_buf += le16_to_cpu(de->rec_len);
2719 	}
2720 
2721 	/* We are careful to leave room for one extra record. */
2722 	return dirent_count < ocfs2_dx_entries_per_root(dir->i_sb);
2723 }
2724 
2725 /*
2726  * Expand rec_len of the rightmost dirent in a directory block so that it
2727  * contains the end of our valid space for dirents. We do this during
2728  * expansion from an inline directory to one with extents. The first dir block
2729  * in that case is taken from the inline data portion of the inode block.
2730  *
2731  * This will also return the largest amount of contiguous space for a dirent
2732  * in the block. That value is *not* necessarily the last dirent, even after
2733  * expansion. The directory indexing code wants this value for free space
2734  * accounting. We do this here since we're already walking the entire dir
2735  * block.
2736  *
2737  * We add the dir trailer if this filesystem wants it.
2738  */
2739 static unsigned int ocfs2_expand_last_dirent(char *start, unsigned int old_size,
2740 					     struct inode *dir)
2741 {
2742 	struct super_block *sb = dir->i_sb;
2743 	struct ocfs2_dir_entry *de;
2744 	struct ocfs2_dir_entry *prev_de;
2745 	char *de_buf, *limit;
2746 	unsigned int new_size = sb->s_blocksize;
2747 	unsigned int bytes, this_hole;
2748 	unsigned int largest_hole = 0;
2749 
2750 	if (ocfs2_new_dir_wants_trailer(dir))
2751 		new_size = ocfs2_dir_trailer_blk_off(sb);
2752 
2753 	bytes = new_size - old_size;
2754 
2755 	limit = start + old_size;
2756 	de_buf = start;
2757 	de = (struct ocfs2_dir_entry *)de_buf;
2758 	do {
2759 		this_hole = ocfs2_figure_dirent_hole(de);
2760 		if (this_hole > largest_hole)
2761 			largest_hole = this_hole;
2762 
2763 		prev_de = de;
2764 		de_buf += le16_to_cpu(de->rec_len);
2765 		de = (struct ocfs2_dir_entry *)de_buf;
2766 	} while (de_buf < limit);
2767 
2768 	le16_add_cpu(&prev_de->rec_len, bytes);
2769 
2770 	/* We need to double check this after modification of the final
2771 	 * dirent. */
2772 	this_hole = ocfs2_figure_dirent_hole(prev_de);
2773 	if (this_hole > largest_hole)
2774 		largest_hole = this_hole;
2775 
2776 	if (largest_hole >= OCFS2_DIR_MIN_REC_LEN)
2777 		return largest_hole;
2778 	return 0;
2779 }
2780 
2781 /*
2782  * We allocate enough clusters to fulfill "blocks_wanted", but set
2783  * i_size to exactly one block. Ocfs2_extend_dir() will handle the
2784  * rest automatically for us.
2785  *
2786  * *first_block_bh is a pointer to the 1st data block allocated to the
2787  *  directory.
2788  */
2789 static int ocfs2_expand_inline_dir(struct inode *dir, struct buffer_head *di_bh,
2790 				   unsigned int blocks_wanted,
2791 				   struct ocfs2_dir_lookup_result *lookup,
2792 				   struct buffer_head **first_block_bh)
2793 {
2794 	u32 alloc, dx_alloc, bit_off, len, num_dx_entries = 0;
2795 	struct super_block *sb = dir->i_sb;
2796 	int ret, i, num_dx_leaves = 0, dx_inline = 0,
2797 		credits = ocfs2_inline_to_extents_credits(sb);
2798 	u64 dx_insert_blkno, blkno,
2799 		bytes = blocks_wanted << sb->s_blocksize_bits;
2800 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
2801 	struct ocfs2_inode_info *oi = OCFS2_I(dir);
2802 	struct ocfs2_alloc_context *data_ac = NULL;
2803 	struct ocfs2_alloc_context *meta_ac = NULL;
2804 	struct buffer_head *dirdata_bh = NULL;
2805 	struct buffer_head *dx_root_bh = NULL;
2806 	struct buffer_head **dx_leaves = NULL;
2807 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
2808 	handle_t *handle;
2809 	struct ocfs2_extent_tree et;
2810 	struct ocfs2_extent_tree dx_et;
2811 	int did_quota = 0, bytes_allocated = 0;
2812 
2813 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(dir), di_bh);
2814 
2815 	alloc = ocfs2_clusters_for_bytes(sb, bytes);
2816 	dx_alloc = 0;
2817 
2818 	down_write(&oi->ip_alloc_sem);
2819 
2820 	if (ocfs2_supports_indexed_dirs(osb)) {
2821 		credits += ocfs2_add_dir_index_credits(sb);
2822 
2823 		dx_inline = ocfs2_new_dx_should_be_inline(dir, di_bh);
2824 		if (!dx_inline) {
2825 			/* Add one more cluster for an index leaf */
2826 			dx_alloc++;
2827 			dx_leaves = ocfs2_dx_dir_kmalloc_leaves(sb,
2828 								&num_dx_leaves);
2829 			if (!dx_leaves) {
2830 				ret = -ENOMEM;
2831 				mlog_errno(ret);
2832 				goto out;
2833 			}
2834 		}
2835 
2836 		/* This gets us the dx_root */
2837 		ret = ocfs2_reserve_new_metadata_blocks(osb, 1, &meta_ac);
2838 		if (ret) {
2839 			mlog_errno(ret);
2840 			goto out;
2841 		}
2842 	}
2843 
2844 	/*
2845 	 * We should never need more than 2 clusters for the unindexed
2846 	 * tree - maximum dirent size is far less than one block. In
2847 	 * fact, the only time we'd need more than one cluster is if
2848 	 * blocksize == clustersize and the dirent won't fit in the
2849 	 * extra space that the expansion to a single block gives. As
2850 	 * of today, that only happens on 4k/4k file systems.
2851 	 */
2852 	BUG_ON(alloc > 2);
2853 
2854 	ret = ocfs2_reserve_clusters(osb, alloc + dx_alloc, &data_ac);
2855 	if (ret) {
2856 		mlog_errno(ret);
2857 		goto out;
2858 	}
2859 
2860 	/*
2861 	 * Prepare for worst case allocation scenario of two separate
2862 	 * extents in the unindexed tree.
2863 	 */
2864 	if (alloc == 2)
2865 		credits += OCFS2_SUBALLOC_ALLOC;
2866 
2867 	handle = ocfs2_start_trans(osb, credits);
2868 	if (IS_ERR(handle)) {
2869 		ret = PTR_ERR(handle);
2870 		mlog_errno(ret);
2871 		goto out;
2872 	}
2873 
2874 	ret = dquot_alloc_space_nodirty(dir,
2875 		ocfs2_clusters_to_bytes(osb->sb, alloc + dx_alloc));
2876 	if (ret)
2877 		goto out_commit;
2878 	did_quota = 1;
2879 
2880 	if (ocfs2_supports_indexed_dirs(osb) && !dx_inline) {
2881 		/*
2882 		 * Allocate our index cluster first, to maximize the
2883 		 * possibility that unindexed leaves grow
2884 		 * contiguously.
2885 		 */
2886 		ret = __ocfs2_dx_dir_new_cluster(dir, 0, handle, data_ac,
2887 						 dx_leaves, num_dx_leaves,
2888 						 &dx_insert_blkno);
2889 		if (ret) {
2890 			mlog_errno(ret);
2891 			goto out_commit;
2892 		}
2893 		bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
2894 	}
2895 
2896 	/*
2897 	 * Try to claim as many clusters as the bitmap can give though
2898 	 * if we only get one now, that's enough to continue. The rest
2899 	 * will be claimed after the conversion to extents.
2900 	 */
2901 	if (ocfs2_dir_resv_allowed(osb))
2902 		data_ac->ac_resv = &oi->ip_la_data_resv;
2903 	ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off, &len);
2904 	if (ret) {
2905 		mlog_errno(ret);
2906 		goto out_commit;
2907 	}
2908 	bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
2909 
2910 	/*
2911 	 * Operations are carefully ordered so that we set up the new
2912 	 * data block first. The conversion from inline data to
2913 	 * extents follows.
2914 	 */
2915 	blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
2916 	dirdata_bh = sb_getblk(sb, blkno);
2917 	if (!dirdata_bh) {
2918 		ret = -ENOMEM;
2919 		mlog_errno(ret);
2920 		goto out_commit;
2921 	}
2922 
2923 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), dirdata_bh);
2924 
2925 	ret = ocfs2_journal_access_db(handle, INODE_CACHE(dir), dirdata_bh,
2926 				      OCFS2_JOURNAL_ACCESS_CREATE);
2927 	if (ret) {
2928 		mlog_errno(ret);
2929 		goto out_commit;
2930 	}
2931 
2932 	memcpy(dirdata_bh->b_data, di->id2.i_data.id_data, i_size_read(dir));
2933 	memset(dirdata_bh->b_data + i_size_read(dir), 0,
2934 	       sb->s_blocksize - i_size_read(dir));
2935 	i = ocfs2_expand_last_dirent(dirdata_bh->b_data, i_size_read(dir), dir);
2936 	if (ocfs2_new_dir_wants_trailer(dir)) {
2937 		/*
2938 		 * Prepare the dir trailer up front. It will otherwise look
2939 		 * like a valid dirent. Even if inserting the index fails
2940 		 * (unlikely), then all we'll have done is given first dir
2941 		 * block a small amount of fragmentation.
2942 		 */
2943 		ocfs2_init_dir_trailer(dir, dirdata_bh, i);
2944 	}
2945 
2946 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
2947 	ocfs2_journal_dirty(handle, dirdata_bh);
2948 
2949 	if (ocfs2_supports_indexed_dirs(osb) && !dx_inline) {
2950 		/*
2951 		 * Dx dirs with an external cluster need to do this up
2952 		 * front. Inline dx root's get handled later, after
2953 		 * we've allocated our root block. We get passed back
2954 		 * a total number of items so that dr_num_entries can
2955 		 * be correctly set once the dx_root has been
2956 		 * allocated.
2957 		 */
2958 		ret = ocfs2_dx_dir_index_block(dir, handle, dx_leaves,
2959 					       num_dx_leaves, &num_dx_entries,
2960 					       dirdata_bh);
2961 		if (ret) {
2962 			mlog_errno(ret);
2963 			goto out_commit;
2964 		}
2965 	}
2966 
2967 	/*
2968 	 * Set extent, i_size, etc on the directory. After this, the
2969 	 * inode should contain the same exact dirents as before and
2970 	 * be fully accessible from system calls.
2971 	 *
2972 	 * We let the later dirent insert modify c/mtime - to the user
2973 	 * the data hasn't changed.
2974 	 */
2975 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
2976 				      OCFS2_JOURNAL_ACCESS_CREATE);
2977 	if (ret) {
2978 		mlog_errno(ret);
2979 		goto out_commit;
2980 	}
2981 
2982 	spin_lock(&oi->ip_lock);
2983 	oi->ip_dyn_features &= ~OCFS2_INLINE_DATA_FL;
2984 	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
2985 	spin_unlock(&oi->ip_lock);
2986 
2987 	ocfs2_dinode_new_extent_list(dir, di);
2988 
2989 	i_size_write(dir, sb->s_blocksize);
2990 	inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
2991 
2992 	di->i_size = cpu_to_le64(sb->s_blocksize);
2993 	di->i_ctime = di->i_mtime = cpu_to_le64(inode_get_ctime_sec(dir));
2994 	di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(inode_get_ctime_nsec(dir));
2995 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
2996 
2997 	/*
2998 	 * This should never fail as our extent list is empty and all
2999 	 * related blocks have been journaled already.
3000 	 */
3001 	ret = ocfs2_insert_extent(handle, &et, 0, blkno, len,
3002 				  0, NULL);
3003 	if (ret) {
3004 		mlog_errno(ret);
3005 		goto out_commit;
3006 	}
3007 
3008 	/*
3009 	 * Set i_blocks after the extent insert for the most up to
3010 	 * date ip_clusters value.
3011 	 */
3012 	dir->i_blocks = ocfs2_inode_sector_count(dir);
3013 
3014 	ocfs2_journal_dirty(handle, di_bh);
3015 
3016 	if (ocfs2_supports_indexed_dirs(osb)) {
3017 		ret = ocfs2_dx_dir_attach_index(osb, handle, dir, di_bh,
3018 						dirdata_bh, meta_ac, dx_inline,
3019 						num_dx_entries, &dx_root_bh);
3020 		if (ret) {
3021 			mlog_errno(ret);
3022 			goto out_commit;
3023 		}
3024 
3025 		if (dx_inline) {
3026 			ocfs2_dx_dir_index_root_block(dir, dx_root_bh,
3027 						      dirdata_bh);
3028 		} else {
3029 			ocfs2_init_dx_root_extent_tree(&dx_et,
3030 						       INODE_CACHE(dir),
3031 						       dx_root_bh);
3032 			ret = ocfs2_insert_extent(handle, &dx_et, 0,
3033 						  dx_insert_blkno, 1, 0, NULL);
3034 			if (ret)
3035 				mlog_errno(ret);
3036 		}
3037 	}
3038 
3039 	/*
3040 	 * We asked for two clusters, but only got one in the 1st
3041 	 * pass. Claim the 2nd cluster as a separate extent.
3042 	 */
3043 	if (alloc > len) {
3044 		ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off,
3045 					   &len);
3046 		if (ret) {
3047 			mlog_errno(ret);
3048 			goto out_commit;
3049 		}
3050 		blkno = ocfs2_clusters_to_blocks(dir->i_sb, bit_off);
3051 
3052 		ret = ocfs2_insert_extent(handle, &et, 1,
3053 					  blkno, len, 0, NULL);
3054 		if (ret) {
3055 			mlog_errno(ret);
3056 			goto out_commit;
3057 		}
3058 		bytes_allocated += ocfs2_clusters_to_bytes(dir->i_sb, 1);
3059 	}
3060 
3061 	*first_block_bh = dirdata_bh;
3062 	dirdata_bh = NULL;
3063 	if (ocfs2_supports_indexed_dirs(osb)) {
3064 		unsigned int off;
3065 
3066 		if (!dx_inline) {
3067 			/*
3068 			 * We need to return the correct block within the
3069 			 * cluster which should hold our entry.
3070 			 */
3071 			off = ocfs2_dx_dir_hash_idx(osb,
3072 						    &lookup->dl_hinfo);
3073 			get_bh(dx_leaves[off]);
3074 			lookup->dl_dx_leaf_bh = dx_leaves[off];
3075 		}
3076 		lookup->dl_dx_root_bh = dx_root_bh;
3077 		dx_root_bh = NULL;
3078 	}
3079 
3080 out_commit:
3081 	if (ret < 0 && did_quota)
3082 		dquot_free_space_nodirty(dir, bytes_allocated);
3083 
3084 	ocfs2_commit_trans(osb, handle);
3085 
3086 out:
3087 	up_write(&oi->ip_alloc_sem);
3088 	if (data_ac)
3089 		ocfs2_free_alloc_context(data_ac);
3090 	if (meta_ac)
3091 		ocfs2_free_alloc_context(meta_ac);
3092 
3093 	if (dx_leaves) {
3094 		for (i = 0; i < num_dx_leaves; i++)
3095 			brelse(dx_leaves[i]);
3096 		kfree(dx_leaves);
3097 	}
3098 
3099 	brelse(dirdata_bh);
3100 	brelse(dx_root_bh);
3101 
3102 	return ret;
3103 }
3104 
3105 /* returns a bh of the 1st new block in the allocation. */
3106 static int ocfs2_do_extend_dir(struct super_block *sb,
3107 			       handle_t *handle,
3108 			       struct inode *dir,
3109 			       struct buffer_head *parent_fe_bh,
3110 			       struct ocfs2_alloc_context *data_ac,
3111 			       struct ocfs2_alloc_context *meta_ac,
3112 			       struct buffer_head **new_bh)
3113 {
3114 	int status;
3115 	int extend, did_quota = 0;
3116 	u64 p_blkno, v_blkno;
3117 
3118 	spin_lock(&OCFS2_I(dir)->ip_lock);
3119 	extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
3120 	spin_unlock(&OCFS2_I(dir)->ip_lock);
3121 
3122 	if (extend) {
3123 		u32 offset = OCFS2_I(dir)->ip_clusters;
3124 
3125 		status = dquot_alloc_space_nodirty(dir,
3126 					ocfs2_clusters_to_bytes(sb, 1));
3127 		if (status)
3128 			goto bail;
3129 		did_quota = 1;
3130 
3131 		status = ocfs2_add_inode_data(OCFS2_SB(sb), dir, &offset,
3132 					      1, 0, parent_fe_bh, handle,
3133 					      data_ac, meta_ac, NULL);
3134 		BUG_ON(status == -EAGAIN);
3135 		if (status < 0) {
3136 			mlog_errno(status);
3137 			goto bail;
3138 		}
3139 	}
3140 
3141 	v_blkno = ocfs2_blocks_for_bytes(sb, i_size_read(dir));
3142 	status = ocfs2_extent_map_get_blocks(dir, v_blkno, &p_blkno, NULL, NULL);
3143 	if (status < 0) {
3144 		mlog_errno(status);
3145 		goto bail;
3146 	}
3147 
3148 	*new_bh = sb_getblk(sb, p_blkno);
3149 	if (!*new_bh) {
3150 		status = -ENOMEM;
3151 		mlog_errno(status);
3152 		goto bail;
3153 	}
3154 	status = 0;
3155 bail:
3156 	if (did_quota && status < 0)
3157 		dquot_free_space_nodirty(dir, ocfs2_clusters_to_bytes(sb, 1));
3158 	return status;
3159 }
3160 
3161 /*
3162  * Assumes you already have a cluster lock on the directory.
3163  *
3164  * 'blocks_wanted' is only used if we have an inline directory which
3165  * is to be turned into an extent based one. The size of the dirent to
3166  * insert might be larger than the space gained by growing to just one
3167  * block, so we may have to grow the inode by two blocks in that case.
3168  *
3169  * If the directory is already indexed, dx_root_bh must be provided.
3170  */
3171 static int ocfs2_extend_dir(struct ocfs2_super *osb,
3172 			    struct inode *dir,
3173 			    struct buffer_head *parent_fe_bh,
3174 			    unsigned int blocks_wanted,
3175 			    struct ocfs2_dir_lookup_result *lookup,
3176 			    struct buffer_head **new_de_bh)
3177 {
3178 	int status = 0;
3179 	int credits, num_free_extents, drop_alloc_sem = 0;
3180 	loff_t dir_i_size;
3181 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
3182 	struct ocfs2_extent_list *el = &fe->id2.i_list;
3183 	struct ocfs2_alloc_context *data_ac = NULL;
3184 	struct ocfs2_alloc_context *meta_ac = NULL;
3185 	handle_t *handle = NULL;
3186 	struct buffer_head *new_bh = NULL;
3187 	struct ocfs2_dir_entry * de;
3188 	struct super_block *sb = osb->sb;
3189 	struct ocfs2_extent_tree et;
3190 	struct buffer_head *dx_root_bh = lookup->dl_dx_root_bh;
3191 
3192 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
3193 		/*
3194 		 * This would be a code error as an inline directory should
3195 		 * never have an index root.
3196 		 */
3197 		BUG_ON(dx_root_bh);
3198 
3199 		status = ocfs2_expand_inline_dir(dir, parent_fe_bh,
3200 						 blocks_wanted, lookup,
3201 						 &new_bh);
3202 		if (status) {
3203 			mlog_errno(status);
3204 			goto bail;
3205 		}
3206 
3207 		/* Expansion from inline to an indexed directory will
3208 		 * have given us this. */
3209 		dx_root_bh = lookup->dl_dx_root_bh;
3210 
3211 		if (blocks_wanted == 1) {
3212 			/*
3213 			 * If the new dirent will fit inside the space
3214 			 * created by pushing out to one block, then
3215 			 * we can complete the operation
3216 			 * here. Otherwise we have to expand i_size
3217 			 * and format the 2nd block below.
3218 			 */
3219 			BUG_ON(new_bh == NULL);
3220 			goto bail_bh;
3221 		}
3222 
3223 		/*
3224 		 * Get rid of 'new_bh' - we want to format the 2nd
3225 		 * data block and return that instead.
3226 		 */
3227 		brelse(new_bh);
3228 		new_bh = NULL;
3229 
3230 		down_write(&OCFS2_I(dir)->ip_alloc_sem);
3231 		drop_alloc_sem = 1;
3232 		dir_i_size = i_size_read(dir);
3233 		credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
3234 		goto do_extend;
3235 	}
3236 
3237 	down_write(&OCFS2_I(dir)->ip_alloc_sem);
3238 	drop_alloc_sem = 1;
3239 	dir_i_size = i_size_read(dir);
3240 	trace_ocfs2_extend_dir((unsigned long long)OCFS2_I(dir)->ip_blkno,
3241 			       dir_i_size);
3242 
3243 	/* dir->i_size is always block aligned. */
3244 	spin_lock(&OCFS2_I(dir)->ip_lock);
3245 	if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
3246 		spin_unlock(&OCFS2_I(dir)->ip_lock);
3247 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(dir),
3248 					      parent_fe_bh);
3249 		num_free_extents = ocfs2_num_free_extents(&et);
3250 		if (num_free_extents < 0) {
3251 			status = num_free_extents;
3252 			mlog_errno(status);
3253 			goto bail;
3254 		}
3255 
3256 		if (!num_free_extents) {
3257 			status = ocfs2_reserve_new_metadata(osb, el, &meta_ac);
3258 			if (status < 0) {
3259 				if (status != -ENOSPC)
3260 					mlog_errno(status);
3261 				goto bail;
3262 			}
3263 		}
3264 
3265 		status = ocfs2_reserve_clusters(osb, 1, &data_ac);
3266 		if (status < 0) {
3267 			if (status != -ENOSPC)
3268 				mlog_errno(status);
3269 			goto bail;
3270 		}
3271 
3272 		if (ocfs2_dir_resv_allowed(osb))
3273 			data_ac->ac_resv = &OCFS2_I(dir)->ip_la_data_resv;
3274 
3275 		credits = ocfs2_calc_extend_credits(sb, el);
3276 	} else {
3277 		spin_unlock(&OCFS2_I(dir)->ip_lock);
3278 		credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
3279 	}
3280 
3281 do_extend:
3282 	if (ocfs2_dir_indexed(dir))
3283 		credits++; /* For attaching the new dirent block to the
3284 			    * dx_root */
3285 
3286 	handle = ocfs2_start_trans(osb, credits);
3287 	if (IS_ERR(handle)) {
3288 		status = PTR_ERR(handle);
3289 		handle = NULL;
3290 		mlog_errno(status);
3291 		goto bail;
3292 	}
3293 
3294 	status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
3295 				     data_ac, meta_ac, &new_bh);
3296 	if (status < 0) {
3297 		mlog_errno(status);
3298 		goto bail;
3299 	}
3300 
3301 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(dir), new_bh);
3302 
3303 	status = ocfs2_journal_access_db(handle, INODE_CACHE(dir), new_bh,
3304 					 OCFS2_JOURNAL_ACCESS_CREATE);
3305 	if (status < 0) {
3306 		mlog_errno(status);
3307 		goto bail;
3308 	}
3309 	memset(new_bh->b_data, 0, sb->s_blocksize);
3310 
3311 	de = (struct ocfs2_dir_entry *) new_bh->b_data;
3312 	de->inode = 0;
3313 	if (ocfs2_supports_dir_trailer(dir)) {
3314 		de->rec_len = cpu_to_le16(ocfs2_dir_trailer_blk_off(sb));
3315 
3316 		ocfs2_init_dir_trailer(dir, new_bh, le16_to_cpu(de->rec_len));
3317 
3318 		if (ocfs2_dir_indexed(dir)) {
3319 			status = ocfs2_dx_dir_link_trailer(dir, handle,
3320 							   dx_root_bh, new_bh);
3321 			if (status) {
3322 				mlog_errno(status);
3323 				goto bail;
3324 			}
3325 		}
3326 	} else {
3327 		de->rec_len = cpu_to_le16(sb->s_blocksize);
3328 	}
3329 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
3330 	ocfs2_journal_dirty(handle, new_bh);
3331 
3332 	dir_i_size += dir->i_sb->s_blocksize;
3333 	i_size_write(dir, dir_i_size);
3334 	dir->i_blocks = ocfs2_inode_sector_count(dir);
3335 	status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
3336 	if (status < 0) {
3337 		mlog_errno(status);
3338 		goto bail;
3339 	}
3340 
3341 bail_bh:
3342 	*new_de_bh = new_bh;
3343 	get_bh(*new_de_bh);
3344 bail:
3345 	if (handle)
3346 		ocfs2_commit_trans(osb, handle);
3347 	if (drop_alloc_sem)
3348 		up_write(&OCFS2_I(dir)->ip_alloc_sem);
3349 
3350 	if (data_ac)
3351 		ocfs2_free_alloc_context(data_ac);
3352 	if (meta_ac)
3353 		ocfs2_free_alloc_context(meta_ac);
3354 
3355 	brelse(new_bh);
3356 
3357 	return status;
3358 }
3359 
3360 static int ocfs2_find_dir_space_id(struct inode *dir, struct buffer_head *di_bh,
3361 				   const char *name, int namelen,
3362 				   struct buffer_head **ret_de_bh,
3363 				   unsigned int *blocks_wanted)
3364 {
3365 	int ret;
3366 	struct super_block *sb = dir->i_sb;
3367 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
3368 	struct ocfs2_dir_entry *de, *last_de = NULL;
3369 	char *first_de, *de_buf, *limit;
3370 	unsigned long offset = 0;
3371 	unsigned int rec_len, new_rec_len, free_space;
3372 
3373 	/*
3374 	 * This calculates how many free bytes we'd have in block zero, should
3375 	 * this function force expansion to an extent tree.
3376 	 */
3377 	if (ocfs2_new_dir_wants_trailer(dir))
3378 		free_space = ocfs2_dir_trailer_blk_off(sb) - i_size_read(dir);
3379 	else
3380 		free_space = dir->i_sb->s_blocksize - i_size_read(dir);
3381 
3382 	first_de = di->id2.i_data.id_data;
3383 	de_buf = first_de;
3384 	limit = de_buf + i_size_read(dir);
3385 	rec_len = OCFS2_DIR_REC_LEN(namelen);
3386 
3387 	while (de_buf < limit) {
3388 		de = (struct ocfs2_dir_entry *)de_buf;
3389 
3390 		if (!ocfs2_check_dir_entry(dir, de, di_bh, first_de,
3391 					   i_size_read(dir), offset)) {
3392 			ret = -ENOENT;
3393 			goto out;
3394 		}
3395 		if (ocfs2_match(namelen, name, de)) {
3396 			ret = -EEXIST;
3397 			goto out;
3398 		}
3399 		/*
3400 		 * No need to check for a trailing dirent record here as
3401 		 * they're not used for inline dirs.
3402 		 */
3403 
3404 		if (ocfs2_dirent_would_fit(de, rec_len)) {
3405 			/* Ok, we found a spot. Return this bh and let
3406 			 * the caller actually fill it in. */
3407 			*ret_de_bh = di_bh;
3408 			get_bh(*ret_de_bh);
3409 			ret = 0;
3410 			goto out;
3411 		}
3412 
3413 		last_de = de;
3414 		de_buf += le16_to_cpu(de->rec_len);
3415 		offset += le16_to_cpu(de->rec_len);
3416 	}
3417 
3418 	/*
3419 	 * We're going to require expansion of the directory - figure
3420 	 * out how many blocks we'll need so that a place for the
3421 	 * dirent can be found.
3422 	 */
3423 	*blocks_wanted = 1;
3424 	new_rec_len = le16_to_cpu(last_de->rec_len) + free_space;
3425 	if (new_rec_len < (rec_len + OCFS2_DIR_REC_LEN(last_de->name_len)))
3426 		*blocks_wanted = 2;
3427 
3428 	ret = -ENOSPC;
3429 out:
3430 	return ret;
3431 }
3432 
3433 static int ocfs2_find_dir_space_el(struct inode *dir, const char *name,
3434 				   int namelen, struct buffer_head **ret_de_bh)
3435 {
3436 	unsigned long offset;
3437 	struct buffer_head *bh = NULL;
3438 	unsigned short rec_len;
3439 	struct ocfs2_dir_entry *de;
3440 	struct super_block *sb = dir->i_sb;
3441 	int status;
3442 	int blocksize = dir->i_sb->s_blocksize;
3443 
3444 	status = ocfs2_read_dir_block(dir, 0, &bh, 0);
3445 	if (status)
3446 		goto bail;
3447 
3448 	rec_len = OCFS2_DIR_REC_LEN(namelen);
3449 	offset = 0;
3450 	de = (struct ocfs2_dir_entry *) bh->b_data;
3451 	while (1) {
3452 		if ((char *)de >= sb->s_blocksize + bh->b_data) {
3453 			brelse(bh);
3454 			bh = NULL;
3455 
3456 			if (i_size_read(dir) <= offset) {
3457 				/*
3458 				 * Caller will have to expand this
3459 				 * directory.
3460 				 */
3461 				status = -ENOSPC;
3462 				goto bail;
3463 			}
3464 			status = ocfs2_read_dir_block(dir,
3465 					     offset >> sb->s_blocksize_bits,
3466 					     &bh, 0);
3467 			if (status)
3468 				goto bail;
3469 
3470 			/* move to next block */
3471 			de = (struct ocfs2_dir_entry *) bh->b_data;
3472 		}
3473 		if (!ocfs2_check_dir_entry(dir, de, bh, bh->b_data, blocksize,
3474 					   offset)) {
3475 			status = -ENOENT;
3476 			goto bail;
3477 		}
3478 		if (ocfs2_match(namelen, name, de)) {
3479 			status = -EEXIST;
3480 			goto bail;
3481 		}
3482 
3483 		if (ocfs2_skip_dir_trailer(dir, de, offset % blocksize,
3484 					   blocksize))
3485 			goto next;
3486 
3487 		if (ocfs2_dirent_would_fit(de, rec_len)) {
3488 			/* Ok, we found a spot. Return this bh and let
3489 			 * the caller actually fill it in. */
3490 			*ret_de_bh = bh;
3491 			get_bh(*ret_de_bh);
3492 			status = 0;
3493 			goto bail;
3494 		}
3495 next:
3496 		offset += le16_to_cpu(de->rec_len);
3497 		de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
3498 	}
3499 
3500 bail:
3501 	brelse(bh);
3502 	if (status)
3503 		mlog_errno(status);
3504 
3505 	return status;
3506 }
3507 
3508 static int dx_leaf_sort_cmp(const void *a, const void *b)
3509 {
3510 	const struct ocfs2_dx_entry *entry1 = a;
3511 	const struct ocfs2_dx_entry *entry2 = b;
3512 	u32 major_hash1 = le32_to_cpu(entry1->dx_major_hash);
3513 	u32 major_hash2 = le32_to_cpu(entry2->dx_major_hash);
3514 	u32 minor_hash1 = le32_to_cpu(entry1->dx_minor_hash);
3515 	u32 minor_hash2 = le32_to_cpu(entry2->dx_minor_hash);
3516 
3517 	if (major_hash1 > major_hash2)
3518 		return 1;
3519 	if (major_hash1 < major_hash2)
3520 		return -1;
3521 
3522 	/*
3523 	 * It is not strictly necessary to sort by minor
3524 	 */
3525 	if (minor_hash1 > minor_hash2)
3526 		return 1;
3527 	if (minor_hash1 < minor_hash2)
3528 		return -1;
3529 	return 0;
3530 }
3531 
3532 static int ocfs2_dx_leaf_same_major(struct ocfs2_dx_leaf *dx_leaf)
3533 {
3534 	struct ocfs2_dx_entry_list *dl_list = &dx_leaf->dl_list;
3535 	int i, num = le16_to_cpu(dl_list->de_num_used);
3536 
3537 	for (i = 0; i < (num - 1); i++) {
3538 		if (le32_to_cpu(dl_list->de_entries[i].dx_major_hash) !=
3539 		    le32_to_cpu(dl_list->de_entries[i + 1].dx_major_hash))
3540 			return 0;
3541 	}
3542 
3543 	return 1;
3544 }
3545 
3546 /*
3547  * Find the optimal value to split this leaf on. This expects the leaf
3548  * entries to be in sorted order.
3549  *
3550  * leaf_cpos is the cpos of the leaf we're splitting. insert_hash is
3551  * the hash we want to insert.
3552  *
3553  * This function is only concerned with the major hash - that which
3554  * determines which cluster an item belongs to.
3555  */
3556 static int ocfs2_dx_dir_find_leaf_split(struct ocfs2_dx_leaf *dx_leaf,
3557 					u32 leaf_cpos, u32 insert_hash,
3558 					u32 *split_hash)
3559 {
3560 	struct ocfs2_dx_entry_list *dl_list = &dx_leaf->dl_list;
3561 	int i, num_used = le16_to_cpu(dl_list->de_num_used);
3562 	int allsame;
3563 
3564 	/*
3565 	 * There's a couple rare, but nasty corner cases we have to
3566 	 * check for here. All of them involve a leaf where all value
3567 	 * have the same hash, which is what we look for first.
3568 	 *
3569 	 * Most of the time, all of the above is false, and we simply
3570 	 * pick the median value for a split.
3571 	 */
3572 	allsame = ocfs2_dx_leaf_same_major(dx_leaf);
3573 	if (allsame) {
3574 		u32 val = le32_to_cpu(dl_list->de_entries[0].dx_major_hash);
3575 
3576 		if (val == insert_hash) {
3577 			/*
3578 			 * No matter where we would choose to split,
3579 			 * the new entry would want to occupy the same
3580 			 * block as these. Since there's no space left
3581 			 * in their existing block, we know there
3582 			 * won't be space after the split.
3583 			 */
3584 			return -ENOSPC;
3585 		}
3586 
3587 		if (val == leaf_cpos) {
3588 			/*
3589 			 * Because val is the same as leaf_cpos (which
3590 			 * is the smallest value this leaf can have),
3591 			 * yet is not equal to insert_hash, then we
3592 			 * know that insert_hash *must* be larger than
3593 			 * val (and leaf_cpos). At least cpos+1 in value.
3594 			 *
3595 			 * We also know then, that there cannot be an
3596 			 * adjacent extent (otherwise we'd be looking
3597 			 * at it). Choosing this value gives us a
3598 			 * chance to get some contiguousness.
3599 			 */
3600 			*split_hash = leaf_cpos + 1;
3601 			return 0;
3602 		}
3603 
3604 		if (val > insert_hash) {
3605 			/*
3606 			 * val can not be the same as insert hash, and
3607 			 * also must be larger than leaf_cpos. Also,
3608 			 * we know that there can't be a leaf between
3609 			 * cpos and val, otherwise the entries with
3610 			 * hash 'val' would be there.
3611 			 */
3612 			*split_hash = val;
3613 			return 0;
3614 		}
3615 
3616 		*split_hash = insert_hash;
3617 		return 0;
3618 	}
3619 
3620 	/*
3621 	 * Since the records are sorted and the checks above
3622 	 * guaranteed that not all records in this block are the same,
3623 	 * we simple travel forward, from the median, and pick the 1st
3624 	 * record whose value is larger than leaf_cpos.
3625 	 */
3626 	for (i = (num_used / 2); i < num_used; i++)
3627 		if (le32_to_cpu(dl_list->de_entries[i].dx_major_hash) >
3628 		    leaf_cpos)
3629 			break;
3630 
3631 	BUG_ON(i == num_used); /* Should be impossible */
3632 	*split_hash = le32_to_cpu(dl_list->de_entries[i].dx_major_hash);
3633 	return 0;
3634 }
3635 
3636 /*
3637  * Transfer all entries in orig_dx_leaves whose major hash is equal to or
3638  * larger than split_hash into new_dx_leaves. We use a temporary
3639  * buffer (tmp_dx_leaf) to make the changes to the original leaf blocks.
3640  *
3641  * Since the block offset inside a leaf (cluster) is a constant mask
3642  * of minor_hash, we can optimize - an item at block offset X within
3643  * the original cluster, will be at offset X within the new cluster.
3644  */
3645 static void ocfs2_dx_dir_transfer_leaf(struct inode *dir, u32 split_hash,
3646 				       handle_t *handle,
3647 				       struct ocfs2_dx_leaf *tmp_dx_leaf,
3648 				       struct buffer_head **orig_dx_leaves,
3649 				       struct buffer_head **new_dx_leaves,
3650 				       int num_dx_leaves)
3651 {
3652 	int i, j, num_used;
3653 	u32 major_hash;
3654 	struct ocfs2_dx_leaf *orig_dx_leaf, *new_dx_leaf;
3655 	struct ocfs2_dx_entry_list *orig_list, *tmp_list;
3656 	struct ocfs2_dx_entry *dx_entry;
3657 
3658 	tmp_list = &tmp_dx_leaf->dl_list;
3659 
3660 	for (i = 0; i < num_dx_leaves; i++) {
3661 		orig_dx_leaf = (struct ocfs2_dx_leaf *) orig_dx_leaves[i]->b_data;
3662 		orig_list = &orig_dx_leaf->dl_list;
3663 		new_dx_leaf = (struct ocfs2_dx_leaf *) new_dx_leaves[i]->b_data;
3664 
3665 		num_used = le16_to_cpu(orig_list->de_num_used);
3666 
3667 		memcpy(tmp_dx_leaf, orig_dx_leaf, dir->i_sb->s_blocksize);
3668 		tmp_list->de_num_used = cpu_to_le16(0);
3669 		memset(&tmp_list->de_entries, 0, sizeof(*dx_entry)*num_used);
3670 
3671 		for (j = 0; j < num_used; j++) {
3672 			dx_entry = &orig_list->de_entries[j];
3673 			major_hash = le32_to_cpu(dx_entry->dx_major_hash);
3674 			if (major_hash >= split_hash)
3675 				ocfs2_dx_dir_leaf_insert_tail(new_dx_leaf,
3676 							      dx_entry);
3677 			else
3678 				ocfs2_dx_dir_leaf_insert_tail(tmp_dx_leaf,
3679 							      dx_entry);
3680 		}
3681 		memcpy(orig_dx_leaf, tmp_dx_leaf, dir->i_sb->s_blocksize);
3682 
3683 		ocfs2_journal_dirty(handle, orig_dx_leaves[i]);
3684 		ocfs2_journal_dirty(handle, new_dx_leaves[i]);
3685 	}
3686 }
3687 
3688 static int ocfs2_dx_dir_rebalance_credits(struct ocfs2_super *osb,
3689 					  struct ocfs2_dx_root_block *dx_root)
3690 {
3691 	int credits = ocfs2_clusters_to_blocks(osb->sb, 3);
3692 
3693 	credits += ocfs2_calc_extend_credits(osb->sb, &dx_root->dr_list);
3694 	credits += ocfs2_quota_trans_credits(osb->sb);
3695 	return credits;
3696 }
3697 
3698 /*
3699  * Find the median value in dx_leaf_bh and allocate a new leaf to move
3700  * half our entries into.
3701  */
3702 static int ocfs2_dx_dir_rebalance(struct ocfs2_super *osb, struct inode *dir,
3703 				  struct buffer_head *dx_root_bh,
3704 				  struct buffer_head *dx_leaf_bh,
3705 				  struct ocfs2_dx_hinfo *hinfo, u32 leaf_cpos,
3706 				  u64 leaf_blkno)
3707 {
3708 	struct ocfs2_dx_leaf *dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
3709 	int credits, ret, i, num_used, did_quota = 0;
3710 	u32 cpos, split_hash, insert_hash = hinfo->major_hash;
3711 	u64 orig_leaves_start;
3712 	int num_dx_leaves;
3713 	struct buffer_head **orig_dx_leaves = NULL;
3714 	struct buffer_head **new_dx_leaves = NULL;
3715 	struct ocfs2_alloc_context *data_ac = NULL, *meta_ac = NULL;
3716 	struct ocfs2_extent_tree et;
3717 	handle_t *handle = NULL;
3718 	struct ocfs2_dx_root_block *dx_root;
3719 	struct ocfs2_dx_leaf *tmp_dx_leaf = NULL;
3720 
3721 	trace_ocfs2_dx_dir_rebalance((unsigned long long)OCFS2_I(dir)->ip_blkno,
3722 				     (unsigned long long)leaf_blkno,
3723 				     insert_hash);
3724 
3725 	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
3726 
3727 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
3728 	/*
3729 	 * XXX: This is a rather large limit. We should use a more
3730 	 * realistic value.
3731 	 */
3732 	if (le32_to_cpu(dx_root->dr_clusters) == UINT_MAX)
3733 		return -ENOSPC;
3734 
3735 	num_used = le16_to_cpu(dx_leaf->dl_list.de_num_used);
3736 	if (num_used < le16_to_cpu(dx_leaf->dl_list.de_count)) {
3737 		mlog(ML_ERROR, "DX Dir: %llu, Asked to rebalance empty leaf: "
3738 		     "%llu, %d\n", (unsigned long long)OCFS2_I(dir)->ip_blkno,
3739 		     (unsigned long long)leaf_blkno, num_used);
3740 		ret = -EIO;
3741 		goto out;
3742 	}
3743 
3744 	orig_dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, &num_dx_leaves);
3745 	if (!orig_dx_leaves) {
3746 		ret = -ENOMEM;
3747 		mlog_errno(ret);
3748 		goto out;
3749 	}
3750 
3751 	new_dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, NULL);
3752 	if (!new_dx_leaves) {
3753 		ret = -ENOMEM;
3754 		mlog_errno(ret);
3755 		goto out;
3756 	}
3757 
3758 	ret = ocfs2_lock_allocators(dir, &et, 1, 0, &data_ac, &meta_ac);
3759 	if (ret) {
3760 		if (ret != -ENOSPC)
3761 			mlog_errno(ret);
3762 		goto out;
3763 	}
3764 
3765 	credits = ocfs2_dx_dir_rebalance_credits(osb, dx_root);
3766 	handle = ocfs2_start_trans(osb, credits);
3767 	if (IS_ERR(handle)) {
3768 		ret = PTR_ERR(handle);
3769 		handle = NULL;
3770 		mlog_errno(ret);
3771 		goto out;
3772 	}
3773 
3774 	ret = dquot_alloc_space_nodirty(dir,
3775 				       ocfs2_clusters_to_bytes(dir->i_sb, 1));
3776 	if (ret)
3777 		goto out_commit;
3778 	did_quota = 1;
3779 
3780 	ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir), dx_leaf_bh,
3781 				      OCFS2_JOURNAL_ACCESS_WRITE);
3782 	if (ret) {
3783 		mlog_errno(ret);
3784 		goto out_commit;
3785 	}
3786 
3787 	/*
3788 	 * This block is changing anyway, so we can sort it in place.
3789 	 */
3790 	sort(dx_leaf->dl_list.de_entries, num_used,
3791 	     sizeof(struct ocfs2_dx_entry), dx_leaf_sort_cmp,
3792 	     NULL);
3793 
3794 	ocfs2_journal_dirty(handle, dx_leaf_bh);
3795 
3796 	ret = ocfs2_dx_dir_find_leaf_split(dx_leaf, leaf_cpos, insert_hash,
3797 					   &split_hash);
3798 	if (ret) {
3799 		mlog_errno(ret);
3800 		goto  out_commit;
3801 	}
3802 
3803 	trace_ocfs2_dx_dir_rebalance_split(leaf_cpos, split_hash, insert_hash);
3804 
3805 	/*
3806 	 * We have to carefully order operations here. There are items
3807 	 * which want to be in the new cluster before insert, but in
3808 	 * order to put those items in the new cluster, we alter the
3809 	 * old cluster. A failure to insert gets nasty.
3810 	 *
3811 	 * So, start by reserving writes to the old
3812 	 * cluster. ocfs2_dx_dir_new_cluster will reserve writes on
3813 	 * the new cluster for us, before inserting it. The insert
3814 	 * won't happen if there's an error before that. Once the
3815 	 * insert is done then, we can transfer from one leaf into the
3816 	 * other without fear of hitting any error.
3817 	 */
3818 
3819 	/*
3820 	 * The leaf transfer wants some scratch space so that we don't
3821 	 * wind up doing a bunch of expensive memmove().
3822 	 */
3823 	tmp_dx_leaf = kmalloc(osb->sb->s_blocksize, GFP_NOFS);
3824 	if (!tmp_dx_leaf) {
3825 		ret = -ENOMEM;
3826 		mlog_errno(ret);
3827 		goto out_commit;
3828 	}
3829 
3830 	orig_leaves_start = ocfs2_block_to_cluster_start(dir->i_sb, leaf_blkno);
3831 	ret = ocfs2_read_dx_leaves(dir, orig_leaves_start, num_dx_leaves,
3832 				   orig_dx_leaves);
3833 	if (ret) {
3834 		mlog_errno(ret);
3835 		goto out_commit;
3836 	}
3837 
3838 	cpos = split_hash;
3839 	ret = ocfs2_dx_dir_new_cluster(dir, &et, cpos, handle,
3840 				       data_ac, meta_ac, new_dx_leaves,
3841 				       num_dx_leaves);
3842 	if (ret) {
3843 		mlog_errno(ret);
3844 		goto out_commit;
3845 	}
3846 
3847 	for (i = 0; i < num_dx_leaves; i++) {
3848 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
3849 					      orig_dx_leaves[i],
3850 					      OCFS2_JOURNAL_ACCESS_WRITE);
3851 		if (ret) {
3852 			mlog_errno(ret);
3853 			goto out_commit;
3854 		}
3855 
3856 		ret = ocfs2_journal_access_dl(handle, INODE_CACHE(dir),
3857 					      new_dx_leaves[i],
3858 					      OCFS2_JOURNAL_ACCESS_WRITE);
3859 		if (ret) {
3860 			mlog_errno(ret);
3861 			goto out_commit;
3862 		}
3863 	}
3864 
3865 	ocfs2_dx_dir_transfer_leaf(dir, split_hash, handle, tmp_dx_leaf,
3866 				   orig_dx_leaves, new_dx_leaves, num_dx_leaves);
3867 
3868 out_commit:
3869 	if (ret < 0 && did_quota)
3870 		dquot_free_space_nodirty(dir,
3871 				ocfs2_clusters_to_bytes(dir->i_sb, 1));
3872 
3873 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
3874 	ocfs2_commit_trans(osb, handle);
3875 
3876 out:
3877 	if (orig_dx_leaves || new_dx_leaves) {
3878 		for (i = 0; i < num_dx_leaves; i++) {
3879 			if (orig_dx_leaves)
3880 				brelse(orig_dx_leaves[i]);
3881 			if (new_dx_leaves)
3882 				brelse(new_dx_leaves[i]);
3883 		}
3884 		kfree(orig_dx_leaves);
3885 		kfree(new_dx_leaves);
3886 	}
3887 
3888 	if (meta_ac)
3889 		ocfs2_free_alloc_context(meta_ac);
3890 	if (data_ac)
3891 		ocfs2_free_alloc_context(data_ac);
3892 
3893 	kfree(tmp_dx_leaf);
3894 	return ret;
3895 }
3896 
3897 static int ocfs2_find_dir_space_dx(struct ocfs2_super *osb, struct inode *dir,
3898 				   struct buffer_head *di_bh,
3899 				   struct buffer_head *dx_root_bh,
3900 				   const char *name, int namelen,
3901 				   struct ocfs2_dir_lookup_result *lookup)
3902 {
3903 	int ret, rebalanced = 0;
3904 	struct ocfs2_dx_root_block *dx_root;
3905 	struct buffer_head *dx_leaf_bh = NULL;
3906 	struct ocfs2_dx_leaf *dx_leaf;
3907 	u64 blkno;
3908 	u32 leaf_cpos;
3909 
3910 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
3911 
3912 restart_search:
3913 	ret = ocfs2_dx_dir_lookup(dir, &dx_root->dr_list, &lookup->dl_hinfo,
3914 				  &leaf_cpos, &blkno);
3915 	if (ret) {
3916 		mlog_errno(ret);
3917 		goto out;
3918 	}
3919 
3920 	ret = ocfs2_read_dx_leaf(dir, blkno, &dx_leaf_bh);
3921 	if (ret) {
3922 		mlog_errno(ret);
3923 		goto out;
3924 	}
3925 
3926 	dx_leaf = (struct ocfs2_dx_leaf *)dx_leaf_bh->b_data;
3927 
3928 	if (le16_to_cpu(dx_leaf->dl_list.de_num_used) >=
3929 	    le16_to_cpu(dx_leaf->dl_list.de_count)) {
3930 		if (rebalanced) {
3931 			/*
3932 			 * Rebalancing should have provided us with
3933 			 * space in an appropriate leaf.
3934 			 *
3935 			 * XXX: Is this an abnormal condition then?
3936 			 * Should we print a message here?
3937 			 */
3938 			ret = -ENOSPC;
3939 			goto out;
3940 		}
3941 
3942 		ret = ocfs2_dx_dir_rebalance(osb, dir, dx_root_bh, dx_leaf_bh,
3943 					     &lookup->dl_hinfo, leaf_cpos,
3944 					     blkno);
3945 		if (ret) {
3946 			if (ret != -ENOSPC)
3947 				mlog_errno(ret);
3948 			goto out;
3949 		}
3950 
3951 		/*
3952 		 * Restart the lookup. The rebalance might have
3953 		 * changed which block our item fits into. Mark our
3954 		 * progress, so we only execute this once.
3955 		 */
3956 		brelse(dx_leaf_bh);
3957 		dx_leaf_bh = NULL;
3958 		rebalanced = 1;
3959 		goto restart_search;
3960 	}
3961 
3962 	lookup->dl_dx_leaf_bh = dx_leaf_bh;
3963 	dx_leaf_bh = NULL;
3964 
3965 out:
3966 	brelse(dx_leaf_bh);
3967 	return ret;
3968 }
3969 
3970 static int ocfs2_search_dx_free_list(struct inode *dir,
3971 				     struct buffer_head *dx_root_bh,
3972 				     int namelen,
3973 				     struct ocfs2_dir_lookup_result *lookup)
3974 {
3975 	int ret = -ENOSPC;
3976 	struct buffer_head *leaf_bh = NULL, *prev_leaf_bh = NULL;
3977 	struct ocfs2_dir_block_trailer *db;
3978 	u64 next_block;
3979 	int rec_len = OCFS2_DIR_REC_LEN(namelen);
3980 	struct ocfs2_dx_root_block *dx_root;
3981 
3982 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
3983 	next_block = le64_to_cpu(dx_root->dr_free_blk);
3984 
3985 	while (next_block) {
3986 		brelse(prev_leaf_bh);
3987 		prev_leaf_bh = leaf_bh;
3988 		leaf_bh = NULL;
3989 
3990 		ret = ocfs2_read_dir_block_direct(dir, next_block, &leaf_bh);
3991 		if (ret) {
3992 			mlog_errno(ret);
3993 			goto out;
3994 		}
3995 
3996 		db = ocfs2_trailer_from_bh(leaf_bh, dir->i_sb);
3997 		if (rec_len <= le16_to_cpu(db->db_free_rec_len)) {
3998 			lookup->dl_leaf_bh = leaf_bh;
3999 			lookup->dl_prev_leaf_bh = prev_leaf_bh;
4000 			leaf_bh = NULL;
4001 			prev_leaf_bh = NULL;
4002 			break;
4003 		}
4004 
4005 		next_block = le64_to_cpu(db->db_free_next);
4006 	}
4007 
4008 	if (!next_block)
4009 		ret = -ENOSPC;
4010 
4011 out:
4012 
4013 	brelse(leaf_bh);
4014 	brelse(prev_leaf_bh);
4015 	return ret;
4016 }
4017 
4018 static int ocfs2_expand_inline_dx_root(struct inode *dir,
4019 				       struct buffer_head *dx_root_bh)
4020 {
4021 	int ret, num_dx_leaves, i, j, did_quota = 0;
4022 	struct buffer_head **dx_leaves = NULL;
4023 	struct ocfs2_extent_tree et;
4024 	u64 insert_blkno;
4025 	struct ocfs2_alloc_context *data_ac = NULL;
4026 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4027 	handle_t *handle = NULL;
4028 	struct ocfs2_dx_root_block *dx_root;
4029 	struct ocfs2_dx_entry_list *entry_list;
4030 	struct ocfs2_dx_entry *dx_entry;
4031 	struct ocfs2_dx_leaf *target_leaf;
4032 
4033 	ret = ocfs2_reserve_clusters(osb, 1, &data_ac);
4034 	if (ret) {
4035 		mlog_errno(ret);
4036 		goto out;
4037 	}
4038 
4039 	dx_leaves = ocfs2_dx_dir_kmalloc_leaves(osb->sb, &num_dx_leaves);
4040 	if (!dx_leaves) {
4041 		ret = -ENOMEM;
4042 		mlog_errno(ret);
4043 		goto out;
4044 	}
4045 
4046 	handle = ocfs2_start_trans(osb, ocfs2_calc_dxi_expand_credits(osb->sb));
4047 	if (IS_ERR(handle)) {
4048 		ret = PTR_ERR(handle);
4049 		mlog_errno(ret);
4050 		goto out;
4051 	}
4052 
4053 	ret = dquot_alloc_space_nodirty(dir,
4054 				       ocfs2_clusters_to_bytes(osb->sb, 1));
4055 	if (ret)
4056 		goto out_commit;
4057 	did_quota = 1;
4058 
4059 	/*
4060 	 * We do this up front, before the allocation, so that a
4061 	 * failure to add the dx_root_bh to the journal won't result
4062 	 * us losing clusters.
4063 	 */
4064 	ret = ocfs2_journal_access_dr(handle, INODE_CACHE(dir), dx_root_bh,
4065 				      OCFS2_JOURNAL_ACCESS_WRITE);
4066 	if (ret) {
4067 		mlog_errno(ret);
4068 		goto out_commit;
4069 	}
4070 
4071 	ret = __ocfs2_dx_dir_new_cluster(dir, 0, handle, data_ac, dx_leaves,
4072 					 num_dx_leaves, &insert_blkno);
4073 	if (ret) {
4074 		mlog_errno(ret);
4075 		goto out_commit;
4076 	}
4077 
4078 	/*
4079 	 * Transfer the entries from our dx_root into the appropriate
4080 	 * block
4081 	 */
4082 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
4083 	entry_list = &dx_root->dr_entries;
4084 
4085 	for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) {
4086 		dx_entry = &entry_list->de_entries[i];
4087 
4088 		j = __ocfs2_dx_dir_hash_idx(osb,
4089 					    le32_to_cpu(dx_entry->dx_minor_hash));
4090 		target_leaf = (struct ocfs2_dx_leaf *)dx_leaves[j]->b_data;
4091 
4092 		ocfs2_dx_dir_leaf_insert_tail(target_leaf, dx_entry);
4093 
4094 		/* Each leaf has been passed to the journal already
4095 		 * via __ocfs2_dx_dir_new_cluster() */
4096 	}
4097 
4098 	dx_root->dr_flags &= ~OCFS2_DX_FLAG_INLINE;
4099 	memset(&dx_root->dr_list, 0, osb->sb->s_blocksize -
4100 	       offsetof(struct ocfs2_dx_root_block, dr_list));
4101 	dx_root->dr_list.l_count =
4102 		cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
4103 
4104 	/* This should never fail considering we start with an empty
4105 	 * dx_root. */
4106 	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
4107 	ret = ocfs2_insert_extent(handle, &et, 0, insert_blkno, 1, 0, NULL);
4108 	if (ret)
4109 		mlog_errno(ret);
4110 	did_quota = 0;
4111 
4112 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
4113 	ocfs2_journal_dirty(handle, dx_root_bh);
4114 
4115 out_commit:
4116 	if (ret < 0 && did_quota)
4117 		dquot_free_space_nodirty(dir,
4118 					  ocfs2_clusters_to_bytes(dir->i_sb, 1));
4119 
4120 	ocfs2_commit_trans(osb, handle);
4121 
4122 out:
4123 	if (data_ac)
4124 		ocfs2_free_alloc_context(data_ac);
4125 
4126 	if (dx_leaves) {
4127 		for (i = 0; i < num_dx_leaves; i++)
4128 			brelse(dx_leaves[i]);
4129 		kfree(dx_leaves);
4130 	}
4131 	return ret;
4132 }
4133 
4134 static int ocfs2_inline_dx_has_space(struct buffer_head *dx_root_bh)
4135 {
4136 	struct ocfs2_dx_root_block *dx_root;
4137 	struct ocfs2_dx_entry_list *entry_list;
4138 
4139 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
4140 	entry_list = &dx_root->dr_entries;
4141 
4142 	if (le16_to_cpu(entry_list->de_num_used) >=
4143 	    le16_to_cpu(entry_list->de_count))
4144 		return -ENOSPC;
4145 
4146 	return 0;
4147 }
4148 
4149 static int ocfs2_prepare_dx_dir_for_insert(struct inode *dir,
4150 					   struct buffer_head *di_bh,
4151 					   const char *name,
4152 					   int namelen,
4153 					   struct ocfs2_dir_lookup_result *lookup)
4154 {
4155 	int ret, free_dx_root = 1;
4156 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4157 	struct buffer_head *dx_root_bh = NULL;
4158 	struct buffer_head *leaf_bh = NULL;
4159 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
4160 	struct ocfs2_dx_root_block *dx_root;
4161 
4162 	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
4163 	if (ret) {
4164 		mlog_errno(ret);
4165 		goto out;
4166 	}
4167 
4168 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
4169 	if (le32_to_cpu(dx_root->dr_num_entries) == OCFS2_DX_ENTRIES_MAX) {
4170 		ret = -ENOSPC;
4171 		mlog_errno(ret);
4172 		goto out;
4173 	}
4174 
4175 	if (ocfs2_dx_root_inline(dx_root)) {
4176 		ret = ocfs2_inline_dx_has_space(dx_root_bh);
4177 
4178 		if (ret == 0)
4179 			goto search_el;
4180 
4181 		/*
4182 		 * We ran out of room in the root block. Expand it to
4183 		 * an extent, then allow ocfs2_find_dir_space_dx to do
4184 		 * the rest.
4185 		 */
4186 		ret = ocfs2_expand_inline_dx_root(dir, dx_root_bh);
4187 		if (ret) {
4188 			mlog_errno(ret);
4189 			goto out;
4190 		}
4191 	}
4192 
4193 	/*
4194 	 * Insert preparation for an indexed directory is split into two
4195 	 * steps. The call to find_dir_space_dx reserves room in the index for
4196 	 * an additional item. If we run out of space there, it's a real error
4197 	 * we can't continue on.
4198 	 */
4199 	ret = ocfs2_find_dir_space_dx(osb, dir, di_bh, dx_root_bh, name,
4200 				      namelen, lookup);
4201 	if (ret) {
4202 		mlog_errno(ret);
4203 		goto out;
4204 	}
4205 
4206 search_el:
4207 	/*
4208 	 * Next, we need to find space in the unindexed tree. This call
4209 	 * searches using the free space linked list. If the unindexed tree
4210 	 * lacks sufficient space, we'll expand it below. The expansion code
4211 	 * is smart enough to add any new blocks to the free space list.
4212 	 */
4213 	ret = ocfs2_search_dx_free_list(dir, dx_root_bh, namelen, lookup);
4214 	if (ret && ret != -ENOSPC) {
4215 		mlog_errno(ret);
4216 		goto out;
4217 	}
4218 
4219 	/* Do this up here - ocfs2_extend_dir might need the dx_root */
4220 	lookup->dl_dx_root_bh = dx_root_bh;
4221 	free_dx_root = 0;
4222 
4223 	if (ret == -ENOSPC) {
4224 		ret = ocfs2_extend_dir(osb, dir, di_bh, 1, lookup, &leaf_bh);
4225 
4226 		if (ret) {
4227 			mlog_errno(ret);
4228 			goto out;
4229 		}
4230 
4231 		/*
4232 		 * We make the assumption here that new leaf blocks are added
4233 		 * to the front of our free list.
4234 		 */
4235 		lookup->dl_prev_leaf_bh = NULL;
4236 		lookup->dl_leaf_bh = leaf_bh;
4237 	}
4238 
4239 out:
4240 	if (free_dx_root)
4241 		brelse(dx_root_bh);
4242 	return ret;
4243 }
4244 
4245 /*
4246  * Get a directory ready for insert. Any directory allocation required
4247  * happens here. Success returns zero, and enough context in the dir
4248  * lookup result that ocfs2_add_entry() will be able complete the task
4249  * with minimal performance impact.
4250  */
4251 int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
4252 				 struct inode *dir,
4253 				 struct buffer_head *parent_fe_bh,
4254 				 const char *name,
4255 				 int namelen,
4256 				 struct ocfs2_dir_lookup_result *lookup)
4257 {
4258 	int ret;
4259 	unsigned int blocks_wanted = 1;
4260 	struct buffer_head *bh = NULL;
4261 
4262 	trace_ocfs2_prepare_dir_for_insert(
4263 		(unsigned long long)OCFS2_I(dir)->ip_blkno, namelen);
4264 
4265 	/*
4266 	 * Do this up front to reduce confusion.
4267 	 *
4268 	 * The directory might start inline, then be turned into an
4269 	 * indexed one, in which case we'd need to hash deep inside
4270 	 * ocfs2_find_dir_space_id(). Since
4271 	 * ocfs2_prepare_dx_dir_for_insert() also needs this hash
4272 	 * done, there seems no point in spreading out the calls. We
4273 	 * can optimize away the case where the file system doesn't
4274 	 * support indexing.
4275 	 */
4276 	if (ocfs2_supports_indexed_dirs(osb))
4277 		ocfs2_dx_dir_name_hash(dir, name, namelen, &lookup->dl_hinfo);
4278 
4279 	if (ocfs2_dir_indexed(dir)) {
4280 		ret = ocfs2_prepare_dx_dir_for_insert(dir, parent_fe_bh,
4281 						      name, namelen, lookup);
4282 		if (ret)
4283 			mlog_errno(ret);
4284 		goto out;
4285 	}
4286 
4287 	if (OCFS2_I(dir)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
4288 		ret = ocfs2_find_dir_space_id(dir, parent_fe_bh, name,
4289 					      namelen, &bh, &blocks_wanted);
4290 	} else
4291 		ret = ocfs2_find_dir_space_el(dir, name, namelen, &bh);
4292 
4293 	if (ret && ret != -ENOSPC) {
4294 		mlog_errno(ret);
4295 		goto out;
4296 	}
4297 
4298 	if (ret == -ENOSPC) {
4299 		/*
4300 		 * We have to expand the directory to add this name.
4301 		 */
4302 		BUG_ON(bh);
4303 
4304 		ret = ocfs2_extend_dir(osb, dir, parent_fe_bh, blocks_wanted,
4305 				       lookup, &bh);
4306 		if (ret) {
4307 			if (ret != -ENOSPC)
4308 				mlog_errno(ret);
4309 			goto out;
4310 		}
4311 
4312 		BUG_ON(!bh);
4313 	}
4314 
4315 	lookup->dl_leaf_bh = bh;
4316 	bh = NULL;
4317 out:
4318 	brelse(bh);
4319 	return ret;
4320 }
4321 
4322 static int ocfs2_dx_dir_remove_index(struct inode *dir,
4323 				     struct buffer_head *di_bh,
4324 				     struct buffer_head *dx_root_bh)
4325 {
4326 	int ret;
4327 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4328 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
4329 	struct ocfs2_dx_root_block *dx_root;
4330 	struct inode *dx_alloc_inode = NULL;
4331 	struct buffer_head *dx_alloc_bh = NULL;
4332 	handle_t *handle;
4333 	u64 blk;
4334 	u16 bit;
4335 	u64 bg_blkno;
4336 
4337 	dx_root = (struct ocfs2_dx_root_block *) dx_root_bh->b_data;
4338 
4339 	dx_alloc_inode = ocfs2_get_system_file_inode(osb,
4340 					EXTENT_ALLOC_SYSTEM_INODE,
4341 					le16_to_cpu(dx_root->dr_suballoc_slot));
4342 	if (!dx_alloc_inode) {
4343 		ret = -ENOMEM;
4344 		mlog_errno(ret);
4345 		goto out;
4346 	}
4347 	inode_lock(dx_alloc_inode);
4348 
4349 	ret = ocfs2_inode_lock(dx_alloc_inode, &dx_alloc_bh, 1);
4350 	if (ret) {
4351 		mlog_errno(ret);
4352 		goto out_mutex;
4353 	}
4354 
4355 	handle = ocfs2_start_trans(osb, OCFS2_DX_ROOT_REMOVE_CREDITS);
4356 	if (IS_ERR(handle)) {
4357 		ret = PTR_ERR(handle);
4358 		mlog_errno(ret);
4359 		goto out_unlock;
4360 	}
4361 
4362 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(dir), di_bh,
4363 				      OCFS2_JOURNAL_ACCESS_WRITE);
4364 	if (ret) {
4365 		mlog_errno(ret);
4366 		goto out_commit;
4367 	}
4368 
4369 	spin_lock(&OCFS2_I(dir)->ip_lock);
4370 	OCFS2_I(dir)->ip_dyn_features &= ~OCFS2_INDEXED_DIR_FL;
4371 	di->i_dyn_features = cpu_to_le16(OCFS2_I(dir)->ip_dyn_features);
4372 	spin_unlock(&OCFS2_I(dir)->ip_lock);
4373 	di->i_dx_root = cpu_to_le64(0ULL);
4374 	ocfs2_update_inode_fsync_trans(handle, dir, 1);
4375 
4376 	ocfs2_journal_dirty(handle, di_bh);
4377 
4378 	blk = le64_to_cpu(dx_root->dr_blkno);
4379 	bit = le16_to_cpu(dx_root->dr_suballoc_bit);
4380 	if (dx_root->dr_suballoc_loc)
4381 		bg_blkno = le64_to_cpu(dx_root->dr_suballoc_loc);
4382 	else
4383 		bg_blkno = ocfs2_which_suballoc_group(blk, bit);
4384 	ret = ocfs2_free_suballoc_bits(handle, dx_alloc_inode, dx_alloc_bh,
4385 				       bit, bg_blkno, 1);
4386 	if (ret)
4387 		mlog_errno(ret);
4388 
4389 out_commit:
4390 	ocfs2_commit_trans(osb, handle);
4391 
4392 out_unlock:
4393 	ocfs2_inode_unlock(dx_alloc_inode, 1);
4394 
4395 out_mutex:
4396 	inode_unlock(dx_alloc_inode);
4397 	brelse(dx_alloc_bh);
4398 out:
4399 	iput(dx_alloc_inode);
4400 	return ret;
4401 }
4402 
4403 int ocfs2_dx_dir_truncate(struct inode *dir, struct buffer_head *di_bh)
4404 {
4405 	int ret;
4406 	unsigned int clen;
4407 	u32 major_hash = UINT_MAX, p_cpos, cpos;
4408 	u64 blkno;
4409 	struct ocfs2_super *osb = OCFS2_SB(dir->i_sb);
4410 	struct buffer_head *dx_root_bh = NULL;
4411 	struct ocfs2_dx_root_block *dx_root;
4412 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
4413 	struct ocfs2_cached_dealloc_ctxt dealloc;
4414 	struct ocfs2_extent_tree et;
4415 
4416 	ocfs2_init_dealloc_ctxt(&dealloc);
4417 
4418 	if (!ocfs2_dir_indexed(dir))
4419 		return 0;
4420 
4421 	ret = ocfs2_read_dx_root(dir, di, &dx_root_bh);
4422 	if (ret) {
4423 		mlog_errno(ret);
4424 		goto out;
4425 	}
4426 	dx_root = (struct ocfs2_dx_root_block *)dx_root_bh->b_data;
4427 
4428 	if (ocfs2_dx_root_inline(dx_root))
4429 		goto remove_index;
4430 
4431 	ocfs2_init_dx_root_extent_tree(&et, INODE_CACHE(dir), dx_root_bh);
4432 
4433 	/* XXX: What if dr_clusters is too large? */
4434 	while (le32_to_cpu(dx_root->dr_clusters)) {
4435 		ret = ocfs2_dx_dir_lookup_rec(dir, &dx_root->dr_list,
4436 					      major_hash, &cpos, &blkno, &clen);
4437 		if (ret) {
4438 			mlog_errno(ret);
4439 			goto out;
4440 		}
4441 
4442 		p_cpos = ocfs2_blocks_to_clusters(dir->i_sb, blkno);
4443 
4444 		ret = ocfs2_remove_btree_range(dir, &et, cpos, p_cpos, clen, 0,
4445 					       &dealloc, 0, false);
4446 		if (ret) {
4447 			mlog_errno(ret);
4448 			goto out;
4449 		}
4450 
4451 		if (cpos == 0)
4452 			break;
4453 
4454 		major_hash = cpos - 1;
4455 	}
4456 
4457 remove_index:
4458 	ret = ocfs2_dx_dir_remove_index(dir, di_bh, dx_root_bh);
4459 	if (ret) {
4460 		mlog_errno(ret);
4461 		goto out;
4462 	}
4463 
4464 	ocfs2_remove_from_cache(INODE_CACHE(dir), dx_root_bh);
4465 out:
4466 	ocfs2_schedule_truncate_log_flush(osb, 1);
4467 	ocfs2_run_deallocs(osb, &dealloc);
4468 
4469 	brelse(dx_root_bh);
4470 	return ret;
4471 }
4472