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1 /*
2  *  linux/fs/ext3/namei.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/namei.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  *  Directory entry file type support and forward compatibility hooks
18  *      for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
19  *  Hash Tree Directory indexing (c)
20  *      Daniel Phillips, 2001
21  *  Hash Tree Directory indexing porting
22  *      Christopher Li, 2002
23  *  Hash Tree Directory indexing cleanup
24  *      Theodore Ts'o, 2002
25  */
26
27 #include <linux/quotaops.h>
28 #include "ext3.h"
29 #include "namei.h"
30 #include "xattr.h"
31 #include "acl.h"
32
33 /*
34  * define how far ahead to read directories while searching them.
35  */
36 #define NAMEI_RA_CHUNKS  2
37 #define NAMEI_RA_BLOCKS  4
38 #define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
39
40 static struct buffer_head *ext3_append(handle_t *handle,
41                                         struct inode *inode,
42                                         u32 *block, int *err)
43 {
44         struct buffer_head *bh;
45
46         *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
47
48         if ((bh = ext3_dir_bread(handle, inode, *block, 1, err))) {
49                 inode->i_size += inode->i_sb->s_blocksize;
50                 EXT3_I(inode)->i_disksize = inode->i_size;
51                 *err = ext3_journal_get_write_access(handle, bh);
52                 if (*err) {
53                         brelse(bh);
54                         bh = NULL;
55                 }
56         }
57         return bh;
58 }
59
60 #ifndef assert
61 #define assert(test) J_ASSERT(test)
62 #endif
63
64 #ifdef DX_DEBUG
65 #define dxtrace(command) command
66 #else
67 #define dxtrace(command)
68 #endif
69
70 struct fake_dirent
71 {
72         __le32 inode;
73         __le16 rec_len;
74         u8 name_len;
75         u8 file_type;
76 };
77
78 struct dx_countlimit
79 {
80         __le16 limit;
81         __le16 count;
82 };
83
84 struct dx_entry
85 {
86         __le32 hash;
87         __le32 block;
88 };
89
90 /*
91  * dx_root_info is laid out so that if it should somehow get overlaid by a
92  * dirent the two low bits of the hash version will be zero.  Therefore, the
93  * hash version mod 4 should never be 0.  Sincerely, the paranoia department.
94  */
95
96 struct dx_root
97 {
98         struct fake_dirent dot;
99         char dot_name[4];
100         struct fake_dirent dotdot;
101         char dotdot_name[4];
102         struct dx_root_info
103         {
104                 __le32 reserved_zero;
105                 u8 hash_version;
106                 u8 info_length; /* 8 */
107                 u8 indirect_levels;
108                 u8 unused_flags;
109         }
110         info;
111         struct dx_entry entries[0];
112 };
113
114 struct dx_node
115 {
116         struct fake_dirent fake;
117         struct dx_entry entries[0];
118 };
119
120
121 struct dx_frame
122 {
123         struct buffer_head *bh;
124         struct dx_entry *entries;
125         struct dx_entry *at;
126 };
127
128 struct dx_map_entry
129 {
130         u32 hash;
131         u16 offs;
132         u16 size;
133 };
134
135 static inline unsigned dx_get_block (struct dx_entry *entry);
136 static void dx_set_block (struct dx_entry *entry, unsigned value);
137 static inline unsigned dx_get_hash (struct dx_entry *entry);
138 static void dx_set_hash (struct dx_entry *entry, unsigned value);
139 static unsigned dx_get_count (struct dx_entry *entries);
140 static unsigned dx_get_limit (struct dx_entry *entries);
141 static void dx_set_count (struct dx_entry *entries, unsigned value);
142 static void dx_set_limit (struct dx_entry *entries, unsigned value);
143 static unsigned dx_root_limit (struct inode *dir, unsigned infosize);
144 static unsigned dx_node_limit (struct inode *dir);
145 static struct dx_frame *dx_probe(struct qstr *entry,
146                                  struct inode *dir,
147                                  struct dx_hash_info *hinfo,
148                                  struct dx_frame *frame,
149                                  int *err);
150 static void dx_release (struct dx_frame *frames);
151 static int dx_make_map(struct ext3_dir_entry_2 *de, unsigned blocksize,
152                         struct dx_hash_info *hinfo, struct dx_map_entry map[]);
153 static void dx_sort_map(struct dx_map_entry *map, unsigned count);
154 static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to,
155                 struct dx_map_entry *offsets, int count);
156 static struct ext3_dir_entry_2 *dx_pack_dirents(char *base, unsigned blocksize);
157 static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block);
158 static int ext3_htree_next_block(struct inode *dir, __u32 hash,
159                                  struct dx_frame *frame,
160                                  struct dx_frame *frames,
161                                  __u32 *start_hash);
162 static struct buffer_head * ext3_dx_find_entry(struct inode *dir,
163                         struct qstr *entry, struct ext3_dir_entry_2 **res_dir,
164                         int *err);
165 static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
166                              struct inode *inode);
167
168 /*
169  * p is at least 6 bytes before the end of page
170  */
171 static inline struct ext3_dir_entry_2 *
172 ext3_next_entry(struct ext3_dir_entry_2 *p)
173 {
174         return (struct ext3_dir_entry_2 *)((char *)p +
175                 ext3_rec_len_from_disk(p->rec_len));
176 }
177
178 /*
179  * Future: use high four bits of block for coalesce-on-delete flags
180  * Mask them off for now.
181  */
182
183 static inline unsigned dx_get_block (struct dx_entry *entry)
184 {
185         return le32_to_cpu(entry->block) & 0x00ffffff;
186 }
187
188 static inline void dx_set_block (struct dx_entry *entry, unsigned value)
189 {
190         entry->block = cpu_to_le32(value);
191 }
192
193 static inline unsigned dx_get_hash (struct dx_entry *entry)
194 {
195         return le32_to_cpu(entry->hash);
196 }
197
198 static inline void dx_set_hash (struct dx_entry *entry, unsigned value)
199 {
200         entry->hash = cpu_to_le32(value);
201 }
202
203 static inline unsigned dx_get_count (struct dx_entry *entries)
204 {
205         return le16_to_cpu(((struct dx_countlimit *) entries)->count);
206 }
207
208 static inline unsigned dx_get_limit (struct dx_entry *entries)
209 {
210         return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
211 }
212
213 static inline void dx_set_count (struct dx_entry *entries, unsigned value)
214 {
215         ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
216 }
217
218 static inline void dx_set_limit (struct dx_entry *entries, unsigned value)
219 {
220         ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
221 }
222
223 static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
224 {
225         unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) -
226                 EXT3_DIR_REC_LEN(2) - infosize;
227         return entry_space / sizeof(struct dx_entry);
228 }
229
230 static inline unsigned dx_node_limit (struct inode *dir)
231 {
232         unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0);
233         return entry_space / sizeof(struct dx_entry);
234 }
235
236 /*
237  * Debug
238  */
239 #ifdef DX_DEBUG
240 static void dx_show_index (char * label, struct dx_entry *entries)
241 {
242         int i, n = dx_get_count (entries);
243         printk("%s index ", label);
244         for (i = 0; i < n; i++)
245         {
246                 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i));
247         }
248         printk("\n");
249 }
250
251 struct stats
252 {
253         unsigned names;
254         unsigned space;
255         unsigned bcount;
256 };
257
258 static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de,
259                                  int size, int show_names)
260 {
261         unsigned names = 0, space = 0;
262         char *base = (char *) de;
263         struct dx_hash_info h = *hinfo;
264
265         printk("names: ");
266         while ((char *) de < base + size)
267         {
268                 if (de->inode)
269                 {
270                         if (show_names)
271                         {
272                                 int len = de->name_len;
273                                 char *name = de->name;
274                                 while (len--) printk("%c", *name++);
275                                 ext3fs_dirhash(de->name, de->name_len, &h);
276                                 printk(":%x.%u ", h.hash,
277                                        (unsigned) ((char *) de - base));
278                         }
279                         space += EXT3_DIR_REC_LEN(de->name_len);
280                         names++;
281                 }
282                 de = ext3_next_entry(de);
283         }
284         printk("(%i)\n", names);
285         return (struct stats) { names, space, 1 };
286 }
287
288 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
289                              struct dx_entry *entries, int levels)
290 {
291         unsigned blocksize = dir->i_sb->s_blocksize;
292         unsigned count = dx_get_count (entries), names = 0, space = 0, i;
293         unsigned bcount = 0;
294         struct buffer_head *bh;
295         int err;
296         printk("%i indexed blocks...\n", count);
297         for (i = 0; i < count; i++, entries++)
298         {
299                 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0;
300                 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
301                 struct stats stats;
302                 printk("%s%3u:%03u hash %8x/%8x ",levels?"":"   ", i, block, hash, range);
303                 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue;
304                 stats = levels?
305                    dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
306                    dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0);
307                 names += stats.names;
308                 space += stats.space;
309                 bcount += stats.bcount;
310                 brelse (bh);
311         }
312         if (bcount)
313                 printk("%snames %u, fullness %u (%u%%)\n", levels?"":"   ",
314                         names, space/bcount,(space/bcount)*100/blocksize);
315         return (struct stats) { names, space, bcount};
316 }
317 #endif /* DX_DEBUG */
318
319 /*
320  * Probe for a directory leaf block to search.
321  *
322  * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
323  * error in the directory index, and the caller should fall back to
324  * searching the directory normally.  The callers of dx_probe **MUST**
325  * check for this error code, and make sure it never gets reflected
326  * back to userspace.
327  */
328 static struct dx_frame *
329 dx_probe(struct qstr *entry, struct inode *dir,
330          struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
331 {
332         unsigned count, indirect;
333         struct dx_entry *at, *entries, *p, *q, *m;
334         struct dx_root *root;
335         struct buffer_head *bh;
336         struct dx_frame *frame = frame_in;
337         u32 hash;
338
339         frame->bh = NULL;
340         if (!(bh = ext3_dir_bread(NULL, dir, 0, 0, err))) {
341                 *err = ERR_BAD_DX_DIR;
342                 goto fail;
343         }
344         root = (struct dx_root *) bh->b_data;
345         if (root->info.hash_version != DX_HASH_TEA &&
346             root->info.hash_version != DX_HASH_HALF_MD4 &&
347             root->info.hash_version != DX_HASH_LEGACY) {
348                 ext3_warning(dir->i_sb, __func__,
349                              "Unrecognised inode hash code %d",
350                              root->info.hash_version);
351                 brelse(bh);
352                 *err = ERR_BAD_DX_DIR;
353                 goto fail;
354         }
355         hinfo->hash_version = root->info.hash_version;
356         if (hinfo->hash_version <= DX_HASH_TEA)
357                 hinfo->hash_version += EXT3_SB(dir->i_sb)->s_hash_unsigned;
358         hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed;
359         if (entry)
360                 ext3fs_dirhash(entry->name, entry->len, hinfo);
361         hash = hinfo->hash;
362
363         if (root->info.unused_flags & 1) {
364                 ext3_warning(dir->i_sb, __func__,
365                              "Unimplemented inode hash flags: %#06x",
366                              root->info.unused_flags);
367                 brelse(bh);
368                 *err = ERR_BAD_DX_DIR;
369                 goto fail;
370         }
371
372         if ((indirect = root->info.indirect_levels) > 1) {
373                 ext3_warning(dir->i_sb, __func__,
374                              "Unimplemented inode hash depth: %#06x",
375                              root->info.indirect_levels);
376                 brelse(bh);
377                 *err = ERR_BAD_DX_DIR;
378                 goto fail;
379         }
380
381         entries = (struct dx_entry *) (((char *)&root->info) +
382                                        root->info.info_length);
383
384         if (dx_get_limit(entries) != dx_root_limit(dir,
385                                                    root->info.info_length)) {
386                 ext3_warning(dir->i_sb, __func__,
387                              "dx entry: limit != root limit");
388                 brelse(bh);
389                 *err = ERR_BAD_DX_DIR;
390                 goto fail;
391         }
392
393         dxtrace (printk("Look up %x", hash));
394         while (1)
395         {
396                 count = dx_get_count(entries);
397                 if (!count || count > dx_get_limit(entries)) {
398                         ext3_warning(dir->i_sb, __func__,
399                                      "dx entry: no count or count > limit");
400                         brelse(bh);
401                         *err = ERR_BAD_DX_DIR;
402                         goto fail2;
403                 }
404
405                 p = entries + 1;
406                 q = entries + count - 1;
407                 while (p <= q)
408                 {
409                         m = p + (q - p)/2;
410                         dxtrace(printk("."));
411                         if (dx_get_hash(m) > hash)
412                                 q = m - 1;
413                         else
414                                 p = m + 1;
415                 }
416
417                 if (0) // linear search cross check
418                 {
419                         unsigned n = count - 1;
420                         at = entries;
421                         while (n--)
422                         {
423                                 dxtrace(printk(","));
424                                 if (dx_get_hash(++at) > hash)
425                                 {
426                                         at--;
427                                         break;
428                                 }
429                         }
430                         assert (at == p - 1);
431                 }
432
433                 at = p - 1;
434                 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
435                 frame->bh = bh;
436                 frame->entries = entries;
437                 frame->at = at;
438                 if (!indirect--) return frame;
439                 if (!(bh = ext3_dir_bread(NULL, dir, dx_get_block(at), 0, err))) {
440                         *err = ERR_BAD_DX_DIR;
441                         goto fail2;
442                 }
443                 at = entries = ((struct dx_node *) bh->b_data)->entries;
444                 if (dx_get_limit(entries) != dx_node_limit (dir)) {
445                         ext3_warning(dir->i_sb, __func__,
446                                      "dx entry: limit != node limit");
447                         brelse(bh);
448                         *err = ERR_BAD_DX_DIR;
449                         goto fail2;
450                 }
451                 frame++;
452                 frame->bh = NULL;
453         }
454 fail2:
455         while (frame >= frame_in) {
456                 brelse(frame->bh);
457                 frame--;
458         }
459 fail:
460         if (*err == ERR_BAD_DX_DIR)
461                 ext3_warning(dir->i_sb, __func__,
462                              "Corrupt dir inode %ld, running e2fsck is "
463                              "recommended.", dir->i_ino);
464         return NULL;
465 }
466
467 static void dx_release (struct dx_frame *frames)
468 {
469         if (frames[0].bh == NULL)
470                 return;
471
472         if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
473                 brelse(frames[1].bh);
474         brelse(frames[0].bh);
475 }
476
477 /*
478  * This function increments the frame pointer to search the next leaf
479  * block, and reads in the necessary intervening nodes if the search
480  * should be necessary.  Whether or not the search is necessary is
481  * controlled by the hash parameter.  If the hash value is even, then
482  * the search is only continued if the next block starts with that
483  * hash value.  This is used if we are searching for a specific file.
484  *
485  * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
486  *
487  * This function returns 1 if the caller should continue to search,
488  * or 0 if it should not.  If there is an error reading one of the
489  * index blocks, it will a negative error code.
490  *
491  * If start_hash is non-null, it will be filled in with the starting
492  * hash of the next page.
493  */
494 static int ext3_htree_next_block(struct inode *dir, __u32 hash,
495                                  struct dx_frame *frame,
496                                  struct dx_frame *frames,
497                                  __u32 *start_hash)
498 {
499         struct dx_frame *p;
500         struct buffer_head *bh;
501         int err, num_frames = 0;
502         __u32 bhash;
503
504         p = frame;
505         /*
506          * Find the next leaf page by incrementing the frame pointer.
507          * If we run out of entries in the interior node, loop around and
508          * increment pointer in the parent node.  When we break out of
509          * this loop, num_frames indicates the number of interior
510          * nodes need to be read.
511          */
512         while (1) {
513                 if (++(p->at) < p->entries + dx_get_count(p->entries))
514                         break;
515                 if (p == frames)
516                         return 0;
517                 num_frames++;
518                 p--;
519         }
520
521         /*
522          * If the hash is 1, then continue only if the next page has a
523          * continuation hash of any value.  This is used for readdir
524          * handling.  Otherwise, check to see if the hash matches the
525          * desired contiuation hash.  If it doesn't, return since
526          * there's no point to read in the successive index pages.
527          */
528         bhash = dx_get_hash(p->at);
529         if (start_hash)
530                 *start_hash = bhash;
531         if ((hash & 1) == 0) {
532                 if ((bhash & ~1) != hash)
533                         return 0;
534         }
535         /*
536          * If the hash is HASH_NB_ALWAYS, we always go to the next
537          * block so no check is necessary
538          */
539         while (num_frames--) {
540                 if (!(bh = ext3_dir_bread(NULL, dir, dx_get_block(p->at),
541                                           0, &err)))
542                         return err; /* Failure */
543                 p++;
544                 brelse (p->bh);
545                 p->bh = bh;
546                 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
547         }
548         return 1;
549 }
550
551
552 /*
553  * This function fills a red-black tree with information from a
554  * directory block.  It returns the number directory entries loaded
555  * into the tree.  If there is an error it is returned in err.
556  */
557 static int htree_dirblock_to_tree(struct file *dir_file,
558                                   struct inode *dir, int block,
559                                   struct dx_hash_info *hinfo,
560                                   __u32 start_hash, __u32 start_minor_hash)
561 {
562         struct buffer_head *bh;
563         struct ext3_dir_entry_2 *de, *top;
564         int err = 0, count = 0;
565
566         dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
567
568         if (!(bh = ext3_dir_bread(NULL, dir, block, 0, &err)))
569                 return err;
570
571         de = (struct ext3_dir_entry_2 *) bh->b_data;
572         top = (struct ext3_dir_entry_2 *) ((char *) de +
573                                            dir->i_sb->s_blocksize -
574                                            EXT3_DIR_REC_LEN(0));
575         for (; de < top; de = ext3_next_entry(de)) {
576                 if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
577                                         (block<<EXT3_BLOCK_SIZE_BITS(dir->i_sb))
578                                                 +((char *)de - bh->b_data))) {
579                         /* silently ignore the rest of the block */
580                         break;
581                 }
582                 ext3fs_dirhash(de->name, de->name_len, hinfo);
583                 if ((hinfo->hash < start_hash) ||
584                     ((hinfo->hash == start_hash) &&
585                      (hinfo->minor_hash < start_minor_hash)))
586                         continue;
587                 if (de->inode == 0)
588                         continue;
589                 if ((err = ext3_htree_store_dirent(dir_file,
590                                    hinfo->hash, hinfo->minor_hash, de)) != 0) {
591                         brelse(bh);
592                         return err;
593                 }
594                 count++;
595         }
596         brelse(bh);
597         return count;
598 }
599
600
601 /*
602  * This function fills a red-black tree with information from a
603  * directory.  We start scanning the directory in hash order, starting
604  * at start_hash and start_minor_hash.
605  *
606  * This function returns the number of entries inserted into the tree,
607  * or a negative error code.
608  */
609 int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
610                          __u32 start_minor_hash, __u32 *next_hash)
611 {
612         struct dx_hash_info hinfo;
613         struct ext3_dir_entry_2 *de;
614         struct dx_frame frames[2], *frame;
615         struct inode *dir;
616         int block, err;
617         int count = 0;
618         int ret;
619         __u32 hashval;
620
621         dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
622                        start_minor_hash));
623         dir = file_inode(dir_file);
624         if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) {
625                 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
626                 if (hinfo.hash_version <= DX_HASH_TEA)
627                         hinfo.hash_version +=
628                                 EXT3_SB(dir->i_sb)->s_hash_unsigned;
629                 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
630                 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
631                                                start_hash, start_minor_hash);
632                 *next_hash = ~0;
633                 return count;
634         }
635         hinfo.hash = start_hash;
636         hinfo.minor_hash = 0;
637         frame = dx_probe(NULL, file_inode(dir_file), &hinfo, frames, &err);
638         if (!frame)
639                 return err;
640
641         /* Add '.' and '..' from the htree header */
642         if (!start_hash && !start_minor_hash) {
643                 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
644                 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0)
645                         goto errout;
646                 count++;
647         }
648         if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
649                 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
650                 de = ext3_next_entry(de);
651                 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0)
652                         goto errout;
653                 count++;
654         }
655
656         while (1) {
657                 block = dx_get_block(frame->at);
658                 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
659                                              start_hash, start_minor_hash);
660                 if (ret < 0) {
661                         err = ret;
662                         goto errout;
663                 }
664                 count += ret;
665                 hashval = ~0;
666                 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS,
667                                             frame, frames, &hashval);
668                 *next_hash = hashval;
669                 if (ret < 0) {
670                         err = ret;
671                         goto errout;
672                 }
673                 /*
674                  * Stop if:  (a) there are no more entries, or
675                  * (b) we have inserted at least one entry and the
676                  * next hash value is not a continuation
677                  */
678                 if ((ret == 0) ||
679                     (count && ((hashval & 1) == 0)))
680                         break;
681         }
682         dx_release(frames);
683         dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n",
684                        count, *next_hash));
685         return count;
686 errout:
687         dx_release(frames);
688         return (err);
689 }
690
691
692 /*
693  * Directory block splitting, compacting
694  */
695
696 /*
697  * Create map of hash values, offsets, and sizes, stored at end of block.
698  * Returns number of entries mapped.
699  */
700 static int dx_make_map(struct ext3_dir_entry_2 *de, unsigned blocksize,
701                 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
702 {
703         int count = 0;
704         char *base = (char *) de;
705         struct dx_hash_info h = *hinfo;
706
707         while ((char *) de < base + blocksize)
708         {
709                 if (de->name_len && de->inode) {
710                         ext3fs_dirhash(de->name, de->name_len, &h);
711                         map_tail--;
712                         map_tail->hash = h.hash;
713                         map_tail->offs = (u16) ((char *) de - base);
714                         map_tail->size = le16_to_cpu(de->rec_len);
715                         count++;
716                         cond_resched();
717                 }
718                 /* XXX: do we need to check rec_len == 0 case? -Chris */
719                 de = ext3_next_entry(de);
720         }
721         return count;
722 }
723
724 /* Sort map by hash value */
725 static void dx_sort_map (struct dx_map_entry *map, unsigned count)
726 {
727         struct dx_map_entry *p, *q, *top = map + count - 1;
728         int more;
729         /* Combsort until bubble sort doesn't suck */
730         while (count > 2)
731         {
732                 count = count*10/13;
733                 if (count - 9 < 2) /* 9, 10 -> 11 */
734                         count = 11;
735                 for (p = top, q = p - count; q >= map; p--, q--)
736                         if (p->hash < q->hash)
737                                 swap(*p, *q);
738         }
739         /* Garden variety bubble sort */
740         do {
741                 more = 0;
742                 q = top;
743                 while (q-- > map)
744                 {
745                         if (q[1].hash >= q[0].hash)
746                                 continue;
747                         swap(*(q+1), *q);
748                         more = 1;
749                 }
750         } while(more);
751 }
752
753 static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
754 {
755         struct dx_entry *entries = frame->entries;
756         struct dx_entry *old = frame->at, *new = old + 1;
757         int count = dx_get_count(entries);
758
759         assert(count < dx_get_limit(entries));
760         assert(old < entries + count);
761         memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
762         dx_set_hash(new, hash);
763         dx_set_block(new, block);
764         dx_set_count(entries, count + 1);
765 }
766
767 static void ext3_update_dx_flag(struct inode *inode)
768 {
769         if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb,
770                                      EXT3_FEATURE_COMPAT_DIR_INDEX))
771                 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL;
772 }
773
774 /*
775  * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure.
776  *
777  * `len <= EXT3_NAME_LEN' is guaranteed by caller.
778  * `de != NULL' is guaranteed by caller.
779  */
780 static inline int ext3_match (int len, const char * const name,
781                               struct ext3_dir_entry_2 * de)
782 {
783         if (len != de->name_len)
784                 return 0;
785         if (!de->inode)
786                 return 0;
787         return !memcmp(name, de->name, len);
788 }
789
790 /*
791  * Returns 0 if not found, -1 on failure, and 1 on success
792  */
793 static inline int search_dirblock(struct buffer_head * bh,
794                                   struct inode *dir,
795                                   struct qstr *child,
796                                   unsigned long offset,
797                                   struct ext3_dir_entry_2 ** res_dir)
798 {
799         struct ext3_dir_entry_2 * de;
800         char * dlimit;
801         int de_len;
802         const char *name = child->name;
803         int namelen = child->len;
804
805         de = (struct ext3_dir_entry_2 *) bh->b_data;
806         dlimit = bh->b_data + dir->i_sb->s_blocksize;
807         while ((char *) de < dlimit) {
808                 /* this code is executed quadratically often */
809                 /* do minimal checking `by hand' */
810
811                 if ((char *) de + namelen <= dlimit &&
812                     ext3_match (namelen, name, de)) {
813                         /* found a match - just to be sure, do a full check */
814                         if (!ext3_check_dir_entry("ext3_find_entry",
815                                                   dir, de, bh, offset))
816                                 return -1;
817                         *res_dir = de;
818                         return 1;
819                 }
820                 /* prevent looping on a bad block */
821                 de_len = ext3_rec_len_from_disk(de->rec_len);
822                 if (de_len <= 0)
823                         return -1;
824                 offset += de_len;
825                 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len);
826         }
827         return 0;
828 }
829
830
831 /*
832  *      ext3_find_entry()
833  *
834  * finds an entry in the specified directory with the wanted name. It
835  * returns the cache buffer in which the entry was found, and the entry
836  * itself (as a parameter - res_dir). It does NOT read the inode of the
837  * entry - you'll have to do that yourself if you want to.
838  *
839  * The returned buffer_head has ->b_count elevated.  The caller is expected
840  * to brelse() it when appropriate.
841  */
842 static struct buffer_head *ext3_find_entry(struct inode *dir,
843                                         struct qstr *entry,
844                                         struct ext3_dir_entry_2 **res_dir)
845 {
846         struct super_block * sb;
847         struct buffer_head * bh_use[NAMEI_RA_SIZE];
848         struct buffer_head * bh, *ret = NULL;
849         unsigned long start, block, b;
850         const u8 *name = entry->name;
851         int ra_max = 0;         /* Number of bh's in the readahead
852                                    buffer, bh_use[] */
853         int ra_ptr = 0;         /* Current index into readahead
854                                    buffer */
855         int num = 0;
856         int nblocks, i, err;
857         int namelen;
858
859         *res_dir = NULL;
860         sb = dir->i_sb;
861         namelen = entry->len;
862         if (namelen > EXT3_NAME_LEN)
863                 return NULL;
864         if ((namelen <= 2) && (name[0] == '.') &&
865             (name[1] == '.' || name[1] == 0)) {
866                 /*
867                  * "." or ".." will only be in the first block
868                  * NFS may look up ".."; "." should be handled by the VFS
869                  */
870                 block = start = 0;
871                 nblocks = 1;
872                 goto restart;
873         }
874         if (is_dx(dir)) {
875                 bh = ext3_dx_find_entry(dir, entry, res_dir, &err);
876                 /*
877                  * On success, or if the error was file not found,
878                  * return.  Otherwise, fall back to doing a search the
879                  * old fashioned way.
880                  */
881                 if (bh || (err != ERR_BAD_DX_DIR))
882                         return bh;
883                 dxtrace(printk("ext3_find_entry: dx failed, falling back\n"));
884         }
885         nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
886         start = EXT3_I(dir)->i_dir_start_lookup;
887         if (start >= nblocks)
888                 start = 0;
889         block = start;
890 restart:
891         do {
892                 /*
893                  * We deal with the read-ahead logic here.
894                  */
895                 if (ra_ptr >= ra_max) {
896                         /* Refill the readahead buffer */
897                         ra_ptr = 0;
898                         b = block;
899                         for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
900                                 /*
901                                  * Terminate if we reach the end of the
902                                  * directory and must wrap, or if our
903                                  * search has finished at this block.
904                                  */
905                                 if (b >= nblocks || (num && block == start)) {
906                                         bh_use[ra_max] = NULL;
907                                         break;
908                                 }
909                                 num++;
910                                 bh = ext3_getblk(NULL, dir, b++, 0, &err);
911                                 bh_use[ra_max] = bh;
912                                 if (bh && !bh_uptodate_or_lock(bh)) {
913                                         get_bh(bh);
914                                         bh->b_end_io = end_buffer_read_sync;
915                                         submit_bh(READ | REQ_META | REQ_PRIO,
916                                                   bh);
917                                 }
918                         }
919                 }
920                 if ((bh = bh_use[ra_ptr++]) == NULL)
921                         goto next;
922                 wait_on_buffer(bh);
923                 if (!buffer_uptodate(bh)) {
924                         /* read error, skip block & hope for the best */
925                         ext3_error(sb, __func__, "reading directory #%lu "
926                                    "offset %lu", dir->i_ino, block);
927                         brelse(bh);
928                         goto next;
929                 }
930                 i = search_dirblock(bh, dir, entry,
931                             block << EXT3_BLOCK_SIZE_BITS(sb), res_dir);
932                 if (i == 1) {
933                         EXT3_I(dir)->i_dir_start_lookup = block;
934                         ret = bh;
935                         goto cleanup_and_exit;
936                 } else {
937                         brelse(bh);
938                         if (i < 0)
939                                 goto cleanup_and_exit;
940                 }
941         next:
942                 if (++block >= nblocks)
943                         block = 0;
944         } while (block != start);
945
946         /*
947          * If the directory has grown while we were searching, then
948          * search the last part of the directory before giving up.
949          */
950         block = nblocks;
951         nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
952         if (block < nblocks) {
953                 start = 0;
954                 goto restart;
955         }
956
957 cleanup_and_exit:
958         /* Clean up the read-ahead blocks */
959         for (; ra_ptr < ra_max; ra_ptr++)
960                 brelse (bh_use[ra_ptr]);
961         return ret;
962 }
963
964 static struct buffer_head * ext3_dx_find_entry(struct inode *dir,
965                         struct qstr *entry, struct ext3_dir_entry_2 **res_dir,
966                         int *err)
967 {
968         struct super_block *sb = dir->i_sb;
969         struct dx_hash_info     hinfo;
970         struct dx_frame frames[2], *frame;
971         struct buffer_head *bh;
972         unsigned long block;
973         int retval;
974
975         if (!(frame = dx_probe(entry, dir, &hinfo, frames, err)))
976                 return NULL;
977         do {
978                 block = dx_get_block(frame->at);
979                 if (!(bh = ext3_dir_bread (NULL, dir, block, 0, err)))
980                         goto errout;
981
982                 retval = search_dirblock(bh, dir, entry,
983                                          block << EXT3_BLOCK_SIZE_BITS(sb),
984                                          res_dir);
985                 if (retval == 1) {
986                         dx_release(frames);
987                         return bh;
988                 }
989                 brelse(bh);
990                 if (retval == -1) {
991                         *err = ERR_BAD_DX_DIR;
992                         goto errout;
993                 }
994
995                 /* Check to see if we should continue to search */
996                 retval = ext3_htree_next_block(dir, hinfo.hash, frame,
997                                                frames, NULL);
998                 if (retval < 0) {
999                         ext3_warning(sb, __func__,
1000                              "error reading index page in directory #%lu",
1001                              dir->i_ino);
1002                         *err = retval;
1003                         goto errout;
1004                 }
1005         } while (retval == 1);
1006
1007         *err = -ENOENT;
1008 errout:
1009         dxtrace(printk("%s not found\n", entry->name));
1010         dx_release (frames);
1011         return NULL;
1012 }
1013
1014 static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)
1015 {
1016         struct inode * inode;
1017         struct ext3_dir_entry_2 * de;
1018         struct buffer_head * bh;
1019
1020         if (dentry->d_name.len > EXT3_NAME_LEN)
1021                 return ERR_PTR(-ENAMETOOLONG);
1022
1023         bh = ext3_find_entry(dir, &dentry->d_name, &de);
1024         inode = NULL;
1025         if (bh) {
1026                 unsigned long ino = le32_to_cpu(de->inode);
1027                 brelse (bh);
1028                 if (!ext3_valid_inum(dir->i_sb, ino)) {
1029                         ext3_error(dir->i_sb, "ext3_lookup",
1030                                    "bad inode number: %lu", ino);
1031                         return ERR_PTR(-EIO);
1032                 }
1033                 inode = ext3_iget(dir->i_sb, ino);
1034                 if (inode == ERR_PTR(-ESTALE)) {
1035                         ext3_error(dir->i_sb, __func__,
1036                                         "deleted inode referenced: %lu",
1037                                         ino);
1038                         return ERR_PTR(-EIO);
1039                 }
1040         }
1041         return d_splice_alias(inode, dentry);
1042 }
1043
1044
1045 struct dentry *ext3_get_parent(struct dentry *child)
1046 {
1047         unsigned long ino;
1048         struct qstr dotdot = QSTR_INIT("..", 2);
1049         struct ext3_dir_entry_2 * de;
1050         struct buffer_head *bh;
1051
1052         bh = ext3_find_entry(child->d_inode, &dotdot, &de);
1053         if (!bh)
1054                 return ERR_PTR(-ENOENT);
1055         ino = le32_to_cpu(de->inode);
1056         brelse(bh);
1057
1058         if (!ext3_valid_inum(child->d_inode->i_sb, ino)) {
1059                 ext3_error(child->d_inode->i_sb, "ext3_get_parent",
1060                            "bad inode number: %lu", ino);
1061                 return ERR_PTR(-EIO);
1062         }
1063
1064         return d_obtain_alias(ext3_iget(child->d_inode->i_sb, ino));
1065 }
1066
1067 #define S_SHIFT 12
1068 static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = {
1069         [S_IFREG >> S_SHIFT]    = EXT3_FT_REG_FILE,
1070         [S_IFDIR >> S_SHIFT]    = EXT3_FT_DIR,
1071         [S_IFCHR >> S_SHIFT]    = EXT3_FT_CHRDEV,
1072         [S_IFBLK >> S_SHIFT]    = EXT3_FT_BLKDEV,
1073         [S_IFIFO >> S_SHIFT]    = EXT3_FT_FIFO,
1074         [S_IFSOCK >> S_SHIFT]   = EXT3_FT_SOCK,
1075         [S_IFLNK >> S_SHIFT]    = EXT3_FT_SYMLINK,
1076 };
1077
1078 static inline void ext3_set_de_type(struct super_block *sb,
1079                                 struct ext3_dir_entry_2 *de,
1080                                 umode_t mode) {
1081         if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE))
1082                 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
1083 }
1084
1085 /*
1086  * Move count entries from end of map between two memory locations.
1087  * Returns pointer to last entry moved.
1088  */
1089 static struct ext3_dir_entry_2 *
1090 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
1091 {
1092         unsigned rec_len = 0;
1093
1094         while (count--) {
1095                 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs);
1096                 rec_len = EXT3_DIR_REC_LEN(de->name_len);
1097                 memcpy (to, de, rec_len);
1098                 ((struct ext3_dir_entry_2 *) to)->rec_len =
1099                                 ext3_rec_len_to_disk(rec_len);
1100                 de->inode = 0;
1101                 map++;
1102                 to += rec_len;
1103         }
1104         return (struct ext3_dir_entry_2 *) (to - rec_len);
1105 }
1106
1107 /*
1108  * Compact each dir entry in the range to the minimal rec_len.
1109  * Returns pointer to last entry in range.
1110  */
1111 static struct ext3_dir_entry_2 *dx_pack_dirents(char *base, unsigned blocksize)
1112 {
1113         struct ext3_dir_entry_2 *next, *to, *prev;
1114         struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *)base;
1115         unsigned rec_len = 0;
1116
1117         prev = to = de;
1118         while ((char *)de < base + blocksize) {
1119                 next = ext3_next_entry(de);
1120                 if (de->inode && de->name_len) {
1121                         rec_len = EXT3_DIR_REC_LEN(de->name_len);
1122                         if (de > to)
1123                                 memmove(to, de, rec_len);
1124                         to->rec_len = ext3_rec_len_to_disk(rec_len);
1125                         prev = to;
1126                         to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len);
1127                 }
1128                 de = next;
1129         }
1130         return prev;
1131 }
1132
1133 /*
1134  * Split a full leaf block to make room for a new dir entry.
1135  * Allocate a new block, and move entries so that they are approx. equally full.
1136  * Returns pointer to de in block into which the new entry will be inserted.
1137  */
1138 static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1139                         struct buffer_head **bh,struct dx_frame *frame,
1140                         struct dx_hash_info *hinfo, int *error)
1141 {
1142         unsigned blocksize = dir->i_sb->s_blocksize;
1143         unsigned count, continued;
1144         struct buffer_head *bh2;
1145         u32 newblock;
1146         u32 hash2;
1147         struct dx_map_entry *map;
1148         char *data1 = (*bh)->b_data, *data2;
1149         unsigned split, move, size;
1150         struct ext3_dir_entry_2 *de = NULL, *de2;
1151         int     err = 0, i;
1152
1153         bh2 = ext3_append (handle, dir, &newblock, &err);
1154         if (!(bh2)) {
1155                 brelse(*bh);
1156                 *bh = NULL;
1157                 goto errout;
1158         }
1159
1160         BUFFER_TRACE(*bh, "get_write_access");
1161         err = ext3_journal_get_write_access(handle, *bh);
1162         if (err)
1163                 goto journal_error;
1164
1165         BUFFER_TRACE(frame->bh, "get_write_access");
1166         err = ext3_journal_get_write_access(handle, frame->bh);
1167         if (err)
1168                 goto journal_error;
1169
1170         data2 = bh2->b_data;
1171
1172         /* create map in the end of data2 block */
1173         map = (struct dx_map_entry *) (data2 + blocksize);
1174         count = dx_make_map ((struct ext3_dir_entry_2 *) data1,
1175                              blocksize, hinfo, map);
1176         map -= count;
1177         dx_sort_map (map, count);
1178         /* Split the existing block in the middle, size-wise */
1179         size = 0;
1180         move = 0;
1181         for (i = count-1; i >= 0; i--) {
1182                 /* is more than half of this entry in 2nd half of the block? */
1183                 if (size + map[i].size/2 > blocksize/2)
1184                         break;
1185                 size += map[i].size;
1186                 move++;
1187         }
1188         /* map index at which we will split */
1189         split = count - move;
1190         hash2 = map[split].hash;
1191         continued = hash2 == map[split - 1].hash;
1192         dxtrace(printk("Split block %i at %x, %i/%i\n",
1193                 dx_get_block(frame->at), hash2, split, count-split));
1194
1195         /* Fancy dance to stay within two buffers */
1196         de2 = dx_move_dirents(data1, data2, map + split, count - split);
1197         de = dx_pack_dirents(data1,blocksize);
1198         de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
1199         de2->rec_len = ext3_rec_len_to_disk(data2 + blocksize - (char *) de2);
1200         dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1));
1201         dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1));
1202
1203         /* Which block gets the new entry? */
1204         if (hinfo->hash >= hash2)
1205         {
1206                 swap(*bh, bh2);
1207                 de = de2;
1208         }
1209         dx_insert_block (frame, hash2 + continued, newblock);
1210         err = ext3_journal_dirty_metadata (handle, bh2);
1211         if (err)
1212                 goto journal_error;
1213         err = ext3_journal_dirty_metadata (handle, frame->bh);
1214         if (err)
1215                 goto journal_error;
1216         brelse (bh2);
1217         dxtrace(dx_show_index ("frame", frame->entries));
1218         return de;
1219
1220 journal_error:
1221         brelse(*bh);
1222         brelse(bh2);
1223         *bh = NULL;
1224         ext3_std_error(dir->i_sb, err);
1225 errout:
1226         *error = err;
1227         return NULL;
1228 }
1229
1230
1231 /*
1232  * Add a new entry into a directory (leaf) block.  If de is non-NULL,
1233  * it points to a directory entry which is guaranteed to be large
1234  * enough for new directory entry.  If de is NULL, then
1235  * add_dirent_to_buf will attempt search the directory block for
1236  * space.  It will return -ENOSPC if no space is available, and -EIO
1237  * and -EEXIST if directory entry already exists.
1238  *
1239  * NOTE!  bh is NOT released in the case where ENOSPC is returned.  In
1240  * all other cases bh is released.
1241  */
1242 static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
1243                              struct inode *inode, struct ext3_dir_entry_2 *de,
1244                              struct buffer_head * bh)
1245 {
1246         struct inode    *dir = dentry->d_parent->d_inode;
1247         const char      *name = dentry->d_name.name;
1248         int             namelen = dentry->d_name.len;
1249         unsigned long   offset = 0;
1250         unsigned short  reclen;
1251         int             nlen, rlen, err;
1252         char            *top;
1253
1254         reclen = EXT3_DIR_REC_LEN(namelen);
1255         if (!de) {
1256                 de = (struct ext3_dir_entry_2 *)bh->b_data;
1257                 top = bh->b_data + dir->i_sb->s_blocksize - reclen;
1258                 while ((char *) de <= top) {
1259                         if (!ext3_check_dir_entry("ext3_add_entry", dir, de,
1260                                                   bh, offset)) {
1261                                 brelse (bh);
1262                                 return -EIO;
1263                         }
1264                         if (ext3_match (namelen, name, de)) {
1265                                 brelse (bh);
1266                                 return -EEXIST;
1267                         }
1268                         nlen = EXT3_DIR_REC_LEN(de->name_len);
1269                         rlen = ext3_rec_len_from_disk(de->rec_len);
1270                         if ((de->inode? rlen - nlen: rlen) >= reclen)
1271                                 break;
1272                         de = (struct ext3_dir_entry_2 *)((char *)de + rlen);
1273                         offset += rlen;
1274                 }
1275                 if ((char *) de > top)
1276                         return -ENOSPC;
1277         }
1278         BUFFER_TRACE(bh, "get_write_access");
1279         err = ext3_journal_get_write_access(handle, bh);
1280         if (err) {
1281                 ext3_std_error(dir->i_sb, err);
1282                 brelse(bh);
1283                 return err;
1284         }
1285
1286         /* By now the buffer is marked for journaling */
1287         nlen = EXT3_DIR_REC_LEN(de->name_len);
1288         rlen = ext3_rec_len_from_disk(de->rec_len);
1289         if (de->inode) {
1290                 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen);
1291                 de1->rec_len = ext3_rec_len_to_disk(rlen - nlen);
1292                 de->rec_len = ext3_rec_len_to_disk(nlen);
1293                 de = de1;
1294         }
1295         de->file_type = EXT3_FT_UNKNOWN;
1296         if (inode) {
1297                 de->inode = cpu_to_le32(inode->i_ino);
1298                 ext3_set_de_type(dir->i_sb, de, inode->i_mode);
1299         } else
1300                 de->inode = 0;
1301         de->name_len = namelen;
1302         memcpy (de->name, name, namelen);
1303         /*
1304          * XXX shouldn't update any times until successful
1305          * completion of syscall, but too many callers depend
1306          * on this.
1307          *
1308          * XXX similarly, too many callers depend on
1309          * ext3_new_inode() setting the times, but error
1310          * recovery deletes the inode, so the worst that can
1311          * happen is that the times are slightly out of date
1312          * and/or different from the directory change time.
1313          */
1314         dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
1315         ext3_update_dx_flag(dir);
1316         dir->i_version++;
1317         ext3_mark_inode_dirty(handle, dir);
1318         BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1319         err = ext3_journal_dirty_metadata(handle, bh);
1320         if (err)
1321                 ext3_std_error(dir->i_sb, err);
1322         brelse(bh);
1323         return 0;
1324 }
1325
1326 /*
1327  * This converts a one block unindexed directory to a 3 block indexed
1328  * directory, and adds the dentry to the indexed directory.
1329  */
1330 static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1331                             struct inode *inode, struct buffer_head *bh)
1332 {
1333         struct inode    *dir = dentry->d_parent->d_inode;
1334         const char      *name = dentry->d_name.name;
1335         int             namelen = dentry->d_name.len;
1336         struct buffer_head *bh2;
1337         struct dx_root  *root;
1338         struct dx_frame frames[2], *frame;
1339         struct dx_entry *entries;
1340         struct ext3_dir_entry_2 *de, *de2;
1341         char            *data1, *top;
1342         unsigned        len;
1343         int             retval;
1344         unsigned        blocksize;
1345         struct dx_hash_info hinfo;
1346         u32             block;
1347         struct fake_dirent *fde;
1348
1349         blocksize =  dir->i_sb->s_blocksize;
1350         dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
1351         retval = ext3_journal_get_write_access(handle, bh);
1352         if (retval) {
1353                 ext3_std_error(dir->i_sb, retval);
1354                 brelse(bh);
1355                 return retval;
1356         }
1357         root = (struct dx_root *) bh->b_data;
1358
1359         /* The 0th block becomes the root, move the dirents out */
1360         fde = &root->dotdot;
1361         de = (struct ext3_dir_entry_2 *)((char *)fde +
1362                         ext3_rec_len_from_disk(fde->rec_len));
1363         if ((char *) de >= (((char *) root) + blocksize)) {
1364                 ext3_error(dir->i_sb, __func__,
1365                            "invalid rec_len for '..' in inode %lu",
1366                            dir->i_ino);
1367                 brelse(bh);
1368                 return -EIO;
1369         }
1370         len = ((char *) root) + blocksize - (char *) de;
1371
1372         bh2 = ext3_append (handle, dir, &block, &retval);
1373         if (!(bh2)) {
1374                 brelse(bh);
1375                 return retval;
1376         }
1377         EXT3_I(dir)->i_flags |= EXT3_INDEX_FL;
1378         data1 = bh2->b_data;
1379
1380         memcpy (data1, de, len);
1381         de = (struct ext3_dir_entry_2 *) data1;
1382         top = data1 + len;
1383         while ((char *)(de2 = ext3_next_entry(de)) < top)
1384                 de = de2;
1385         de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
1386         /* Initialize the root; the dot dirents already exist */
1387         de = (struct ext3_dir_entry_2 *) (&root->dotdot);
1388         de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2));
1389         memset (&root->info, 0, sizeof(root->info));
1390         root->info.info_length = sizeof(root->info);
1391         root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
1392         entries = root->entries;
1393         dx_set_block (entries, 1);
1394         dx_set_count (entries, 1);
1395         dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));
1396
1397         /* Initialize as for dx_probe */
1398         hinfo.hash_version = root->info.hash_version;
1399         if (hinfo.hash_version <= DX_HASH_TEA)
1400                 hinfo.hash_version += EXT3_SB(dir->i_sb)->s_hash_unsigned;
1401         hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
1402         ext3fs_dirhash(name, namelen, &hinfo);
1403         frame = frames;
1404         frame->entries = entries;
1405         frame->at = entries;
1406         frame->bh = bh;
1407         bh = bh2;
1408         /*
1409          * Mark buffers dirty here so that if do_split() fails we write a
1410          * consistent set of buffers to disk.
1411          */
1412         ext3_journal_dirty_metadata(handle, frame->bh);
1413         ext3_journal_dirty_metadata(handle, bh);
1414         de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
1415         if (!de) {
1416                 ext3_mark_inode_dirty(handle, dir);
1417                 dx_release(frames);
1418                 return retval;
1419         }
1420         dx_release(frames);
1421
1422         return add_dirent_to_buf(handle, dentry, inode, de, bh);
1423 }
1424
1425 /*
1426  *      ext3_add_entry()
1427  *
1428  * adds a file entry to the specified directory, using the same
1429  * semantics as ext3_find_entry(). It returns NULL if it failed.
1430  *
1431  * NOTE!! The inode part of 'de' is left at 0 - which means you
1432  * may not sleep between calling this and putting something into
1433  * the entry, as someone else might have used it while you slept.
1434  */
1435 static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
1436         struct inode *inode)
1437 {
1438         struct inode *dir = dentry->d_parent->d_inode;
1439         struct buffer_head * bh;
1440         struct ext3_dir_entry_2 *de;
1441         struct super_block * sb;
1442         int     retval;
1443         int     dx_fallback=0;
1444         unsigned blocksize;
1445         u32 block, blocks;
1446
1447         sb = dir->i_sb;
1448         blocksize = sb->s_blocksize;
1449         if (!dentry->d_name.len)
1450                 return -EINVAL;
1451         if (is_dx(dir)) {
1452                 retval = ext3_dx_add_entry(handle, dentry, inode);
1453                 if (!retval || (retval != ERR_BAD_DX_DIR))
1454                         return retval;
1455                 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL;
1456                 dx_fallback++;
1457                 ext3_mark_inode_dirty(handle, dir);
1458         }
1459         blocks = dir->i_size >> sb->s_blocksize_bits;
1460         for (block = 0; block < blocks; block++) {
1461                 if (!(bh = ext3_dir_bread(handle, dir, block, 0, &retval)))
1462                         return retval;
1463
1464                 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1465                 if (retval != -ENOSPC)
1466                         return retval;
1467
1468                 if (blocks == 1 && !dx_fallback &&
1469                     EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
1470                         return make_indexed_dir(handle, dentry, inode, bh);
1471                 brelse(bh);
1472         }
1473         bh = ext3_append(handle, dir, &block, &retval);
1474         if (!bh)
1475                 return retval;
1476         de = (struct ext3_dir_entry_2 *) bh->b_data;
1477         de->inode = 0;
1478         de->rec_len = ext3_rec_len_to_disk(blocksize);
1479         return add_dirent_to_buf(handle, dentry, inode, de, bh);
1480 }
1481
1482 /*
1483  * Returns 0 for success, or a negative error value
1484  */
1485 static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
1486                              struct inode *inode)
1487 {
1488         struct dx_frame frames[2], *frame;
1489         struct dx_entry *entries, *at;
1490         struct dx_hash_info hinfo;
1491         struct buffer_head * bh;
1492         struct inode *dir = dentry->d_parent->d_inode;
1493         struct super_block * sb = dir->i_sb;
1494         struct ext3_dir_entry_2 *de;
1495         int err;
1496
1497         frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err);
1498         if (!frame)
1499                 return err;
1500         entries = frame->entries;
1501         at = frame->at;
1502
1503         if (!(bh = ext3_dir_bread(handle, dir, dx_get_block(frame->at), 0, &err)))
1504                 goto cleanup;
1505
1506         BUFFER_TRACE(bh, "get_write_access");
1507         err = ext3_journal_get_write_access(handle, bh);
1508         if (err)
1509                 goto journal_error;
1510
1511         err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1512         if (err != -ENOSPC) {
1513                 bh = NULL;
1514                 goto cleanup;
1515         }
1516
1517         /* Block full, should compress but for now just split */
1518         dxtrace(printk("using %u of %u node entries\n",
1519                        dx_get_count(entries), dx_get_limit(entries)));
1520         /* Need to split index? */
1521         if (dx_get_count(entries) == dx_get_limit(entries)) {
1522                 u32 newblock;
1523                 unsigned icount = dx_get_count(entries);
1524                 int levels = frame - frames;
1525                 struct dx_entry *entries2;
1526                 struct dx_node *node2;
1527                 struct buffer_head *bh2;
1528
1529                 if (levels && (dx_get_count(frames->entries) ==
1530                                dx_get_limit(frames->entries))) {
1531                         ext3_warning(sb, __func__,
1532                                      "Directory index full!");
1533                         err = -ENOSPC;
1534                         goto cleanup;
1535                 }
1536                 bh2 = ext3_append (handle, dir, &newblock, &err);
1537                 if (!(bh2))
1538                         goto cleanup;
1539                 node2 = (struct dx_node *)(bh2->b_data);
1540                 entries2 = node2->entries;
1541                 memset(&node2->fake, 0, sizeof(struct fake_dirent));
1542                 node2->fake.rec_len = ext3_rec_len_to_disk(sb->s_blocksize);
1543                 BUFFER_TRACE(frame->bh, "get_write_access");
1544                 err = ext3_journal_get_write_access(handle, frame->bh);
1545                 if (err)
1546                         goto journal_error;
1547                 if (levels) {
1548                         unsigned icount1 = icount/2, icount2 = icount - icount1;
1549                         unsigned hash2 = dx_get_hash(entries + icount1);
1550                         dxtrace(printk("Split index %i/%i\n", icount1, icount2));
1551
1552                         BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
1553                         err = ext3_journal_get_write_access(handle,
1554                                                              frames[0].bh);
1555                         if (err)
1556                                 goto journal_error;
1557
1558                         memcpy ((char *) entries2, (char *) (entries + icount1),
1559                                 icount2 * sizeof(struct dx_entry));
1560                         dx_set_count (entries, icount1);
1561                         dx_set_count (entries2, icount2);
1562                         dx_set_limit (entries2, dx_node_limit(dir));
1563
1564                         /* Which index block gets the new entry? */
1565                         if (at - entries >= icount1) {
1566                                 frame->at = at = at - entries - icount1 + entries2;
1567                                 frame->entries = entries = entries2;
1568                                 swap(frame->bh, bh2);
1569                         }
1570                         dx_insert_block (frames + 0, hash2, newblock);
1571                         dxtrace(dx_show_index ("node", frames[1].entries));
1572                         dxtrace(dx_show_index ("node",
1573                                ((struct dx_node *) bh2->b_data)->entries));
1574                         err = ext3_journal_dirty_metadata(handle, bh2);
1575                         if (err)
1576                                 goto journal_error;
1577                         brelse (bh2);
1578                 } else {
1579                         dxtrace(printk("Creating second level index...\n"));
1580                         memcpy((char *) entries2, (char *) entries,
1581                                icount * sizeof(struct dx_entry));
1582                         dx_set_limit(entries2, dx_node_limit(dir));
1583
1584                         /* Set up root */
1585                         dx_set_count(entries, 1);
1586                         dx_set_block(entries + 0, newblock);
1587                         ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
1588
1589                         /* Add new access path frame */
1590                         frame = frames + 1;
1591                         frame->at = at = at - entries + entries2;
1592                         frame->entries = entries = entries2;
1593                         frame->bh = bh2;
1594                         err = ext3_journal_get_write_access(handle,
1595                                                              frame->bh);
1596                         if (err)
1597                                 goto journal_error;
1598                 }
1599                 err = ext3_journal_dirty_metadata(handle, frames[0].bh);
1600                 if (err)
1601                         goto journal_error;
1602         }
1603         de = do_split(handle, dir, &bh, frame, &hinfo, &err);
1604         if (!de)
1605                 goto cleanup;
1606         err = add_dirent_to_buf(handle, dentry, inode, de, bh);
1607         bh = NULL;
1608         goto cleanup;
1609
1610 journal_error:
1611         ext3_std_error(dir->i_sb, err);
1612 cleanup:
1613         if (bh)
1614                 brelse(bh);
1615         dx_release(frames);
1616         return err;
1617 }
1618
1619 /*
1620  * ext3_delete_entry deletes a directory entry by merging it with the
1621  * previous entry
1622  */
1623 static int ext3_delete_entry (handle_t *handle,
1624                               struct inode * dir,
1625                               struct ext3_dir_entry_2 * de_del,
1626                               struct buffer_head * bh)
1627 {
1628         struct ext3_dir_entry_2 * de, * pde;
1629         int i;
1630
1631         i = 0;
1632         pde = NULL;
1633         de = (struct ext3_dir_entry_2 *) bh->b_data;
1634         while (i < bh->b_size) {
1635                 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i))
1636                         return -EIO;
1637                 if (de == de_del)  {
1638                         int err;
1639
1640                         BUFFER_TRACE(bh, "get_write_access");
1641                         err = ext3_journal_get_write_access(handle, bh);
1642                         if (err)
1643                                 goto journal_error;
1644
1645                         if (pde)
1646                                 pde->rec_len = ext3_rec_len_to_disk(
1647                                         ext3_rec_len_from_disk(pde->rec_len) +
1648                                         ext3_rec_len_from_disk(de->rec_len));
1649                         else
1650                                 de->inode = 0;
1651                         dir->i_version++;
1652                         BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1653                         err = ext3_journal_dirty_metadata(handle, bh);
1654                         if (err) {
1655 journal_error:
1656                                 ext3_std_error(dir->i_sb, err);
1657                                 return err;
1658                         }
1659                         return 0;
1660                 }
1661                 i += ext3_rec_len_from_disk(de->rec_len);
1662                 pde = de;
1663                 de = ext3_next_entry(de);
1664         }
1665         return -ENOENT;
1666 }
1667
1668 static int ext3_add_nondir(handle_t *handle,
1669                 struct dentry *dentry, struct inode *inode)
1670 {
1671         int err = ext3_add_entry(handle, dentry, inode);
1672         if (!err) {
1673                 ext3_mark_inode_dirty(handle, inode);
1674                 unlock_new_inode(inode);
1675                 d_instantiate(dentry, inode);
1676                 return 0;
1677         }
1678         drop_nlink(inode);
1679         unlock_new_inode(inode);
1680         iput(inode);
1681         return err;
1682 }
1683
1684 /*
1685  * By the time this is called, we already have created
1686  * the directory cache entry for the new file, but it
1687  * is so far negative - it has no inode.
1688  *
1689  * If the create succeeds, we fill in the inode information
1690  * with d_instantiate().
1691  */
1692 static int ext3_create (struct inode * dir, struct dentry * dentry, umode_t mode,
1693                 bool excl)
1694 {
1695         handle_t *handle;
1696         struct inode * inode;
1697         int err, retries = 0;
1698
1699         dquot_initialize(dir);
1700
1701 retry:
1702         handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
1703                                         EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1704                                         EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
1705         if (IS_ERR(handle))
1706                 return PTR_ERR(handle);
1707
1708         if (IS_DIRSYNC(dir))
1709                 handle->h_sync = 1;
1710
1711         inode = ext3_new_inode (handle, dir, &dentry->d_name, mode);
1712         err = PTR_ERR(inode);
1713         if (!IS_ERR(inode)) {
1714                 inode->i_op = &ext3_file_inode_operations;
1715                 inode->i_fop = &ext3_file_operations;
1716                 ext3_set_aops(inode);
1717                 err = ext3_add_nondir(handle, dentry, inode);
1718         }
1719         ext3_journal_stop(handle);
1720         if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1721                 goto retry;
1722         return err;
1723 }
1724
1725 static int ext3_mknod (struct inode * dir, struct dentry *dentry,
1726                         umode_t mode, dev_t rdev)
1727 {
1728         handle_t *handle;
1729         struct inode *inode;
1730         int err, retries = 0;
1731
1732         if (!new_valid_dev(rdev))
1733                 return -EINVAL;
1734
1735         dquot_initialize(dir);
1736
1737 retry:
1738         handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
1739                                         EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1740                                         EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
1741         if (IS_ERR(handle))
1742                 return PTR_ERR(handle);
1743
1744         if (IS_DIRSYNC(dir))
1745                 handle->h_sync = 1;
1746
1747         inode = ext3_new_inode (handle, dir, &dentry->d_name, mode);
1748         err = PTR_ERR(inode);
1749         if (!IS_ERR(inode)) {
1750                 init_special_inode(inode, inode->i_mode, rdev);
1751 #ifdef CONFIG_EXT3_FS_XATTR
1752                 inode->i_op = &ext3_special_inode_operations;
1753 #endif
1754                 err = ext3_add_nondir(handle, dentry, inode);
1755         }
1756         ext3_journal_stop(handle);
1757         if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1758                 goto retry;
1759         return err;
1760 }
1761
1762 static int ext3_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
1763 {
1764         handle_t *handle;
1765         struct inode *inode;
1766         int err, retries = 0;
1767
1768         dquot_initialize(dir);
1769
1770 retry:
1771         handle = ext3_journal_start(dir, EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
1772                           4 + EXT3_XATTR_TRANS_BLOCKS);
1773
1774         if (IS_ERR(handle))
1775                 return PTR_ERR(handle);
1776
1777         inode = ext3_new_inode (handle, dir, NULL, mode);
1778         err = PTR_ERR(inode);
1779         if (!IS_ERR(inode)) {
1780                 inode->i_op = &ext3_file_inode_operations;
1781                 inode->i_fop = &ext3_file_operations;
1782                 ext3_set_aops(inode);
1783                 d_tmpfile(dentry, inode);
1784                 err = ext3_orphan_add(handle, inode);
1785                 if (err)
1786                         goto err_drop_inode;
1787                 mark_inode_dirty(inode);
1788                 unlock_new_inode(inode);
1789         }
1790         ext3_journal_stop(handle);
1791         if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1792                 goto retry;
1793         return err;
1794 err_drop_inode:
1795         ext3_journal_stop(handle);
1796         unlock_new_inode(inode);
1797         iput(inode);
1798         return err;
1799 }
1800
1801 static int ext3_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
1802 {
1803         handle_t *handle;
1804         struct inode * inode;
1805         struct buffer_head * dir_block = NULL;
1806         struct ext3_dir_entry_2 * de;
1807         int err, retries = 0;
1808
1809         if (dir->i_nlink >= EXT3_LINK_MAX)
1810                 return -EMLINK;
1811
1812         dquot_initialize(dir);
1813
1814 retry:
1815         handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
1816                                         EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1817                                         EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
1818         if (IS_ERR(handle))
1819                 return PTR_ERR(handle);
1820
1821         if (IS_DIRSYNC(dir))
1822                 handle->h_sync = 1;
1823
1824         inode = ext3_new_inode (handle, dir, &dentry->d_name, S_IFDIR | mode);
1825         err = PTR_ERR(inode);
1826         if (IS_ERR(inode))
1827                 goto out_stop;
1828
1829         inode->i_op = &ext3_dir_inode_operations;
1830         inode->i_fop = &ext3_dir_operations;
1831         inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1832         if (!(dir_block = ext3_dir_bread(handle, inode, 0, 1, &err)))
1833                 goto out_clear_inode;
1834
1835         BUFFER_TRACE(dir_block, "get_write_access");
1836         err = ext3_journal_get_write_access(handle, dir_block);
1837         if (err)
1838                 goto out_clear_inode;
1839
1840         de = (struct ext3_dir_entry_2 *) dir_block->b_data;
1841         de->inode = cpu_to_le32(inode->i_ino);
1842         de->name_len = 1;
1843         de->rec_len = ext3_rec_len_to_disk(EXT3_DIR_REC_LEN(de->name_len));
1844         strcpy (de->name, ".");
1845         ext3_set_de_type(dir->i_sb, de, S_IFDIR);
1846         de = ext3_next_entry(de);
1847         de->inode = cpu_to_le32(dir->i_ino);
1848         de->rec_len = ext3_rec_len_to_disk(inode->i_sb->s_blocksize -
1849                                         EXT3_DIR_REC_LEN(1));
1850         de->name_len = 2;
1851         strcpy (de->name, "..");
1852         ext3_set_de_type(dir->i_sb, de, S_IFDIR);
1853         set_nlink(inode, 2);
1854         BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata");
1855         err = ext3_journal_dirty_metadata(handle, dir_block);
1856         if (err)
1857                 goto out_clear_inode;
1858
1859         err = ext3_mark_inode_dirty(handle, inode);
1860         if (!err)
1861                 err = ext3_add_entry (handle, dentry, inode);
1862
1863         if (err) {
1864 out_clear_inode:
1865                 clear_nlink(inode);
1866                 unlock_new_inode(inode);
1867                 ext3_mark_inode_dirty(handle, inode);
1868                 iput (inode);
1869                 goto out_stop;
1870         }
1871         inc_nlink(dir);
1872         ext3_update_dx_flag(dir);
1873         err = ext3_mark_inode_dirty(handle, dir);
1874         if (err)
1875                 goto out_clear_inode;
1876
1877         unlock_new_inode(inode);
1878         d_instantiate(dentry, inode);
1879 out_stop:
1880         brelse(dir_block);
1881         ext3_journal_stop(handle);
1882         if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1883                 goto retry;
1884         return err;
1885 }
1886
1887 /*
1888  * routine to check that the specified directory is empty (for rmdir)
1889  */
1890 static int empty_dir (struct inode * inode)
1891 {
1892         unsigned long offset;
1893         struct buffer_head * bh;
1894         struct ext3_dir_entry_2 * de, * de1;
1895         struct super_block * sb;
1896         int err = 0;
1897
1898         sb = inode->i_sb;
1899         if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) ||
1900             !(bh = ext3_dir_bread(NULL, inode, 0, 0, &err))) {
1901                 if (err)
1902                         ext3_error(inode->i_sb, __func__,
1903                                    "error %d reading directory #%lu offset 0",
1904                                    err, inode->i_ino);
1905                 else
1906                         ext3_warning(inode->i_sb, __func__,
1907                                      "bad directory (dir #%lu) - no data block",
1908                                      inode->i_ino);
1909                 return 1;
1910         }
1911         de = (struct ext3_dir_entry_2 *) bh->b_data;
1912         de1 = ext3_next_entry(de);
1913         if (le32_to_cpu(de->inode) != inode->i_ino ||
1914                         !le32_to_cpu(de1->inode) ||
1915                         strcmp (".", de->name) ||
1916                         strcmp ("..", de1->name)) {
1917                 ext3_warning (inode->i_sb, "empty_dir",
1918                               "bad directory (dir #%lu) - no `.' or `..'",
1919                               inode->i_ino);
1920                 brelse (bh);
1921                 return 1;
1922         }
1923         offset = ext3_rec_len_from_disk(de->rec_len) +
1924                         ext3_rec_len_from_disk(de1->rec_len);
1925         de = ext3_next_entry(de1);
1926         while (offset < inode->i_size ) {
1927                 if (!bh ||
1928                         (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
1929                         err = 0;
1930                         brelse (bh);
1931                         if (!(bh = ext3_dir_bread (NULL, inode,
1932                                 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err))) {
1933                                 if (err)
1934                                         ext3_error(sb, __func__,
1935                                                    "error %d reading directory"
1936                                                    " #%lu offset %lu",
1937                                                    err, inode->i_ino, offset);
1938                                 offset += sb->s_blocksize;
1939                                 continue;
1940                         }
1941                         de = (struct ext3_dir_entry_2 *) bh->b_data;
1942                 }
1943                 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) {
1944                         de = (struct ext3_dir_entry_2 *)(bh->b_data +
1945                                                          sb->s_blocksize);
1946                         offset = (offset | (sb->s_blocksize - 1)) + 1;
1947                         continue;
1948                 }
1949                 if (le32_to_cpu(de->inode)) {
1950                         brelse (bh);
1951                         return 0;
1952                 }
1953                 offset += ext3_rec_len_from_disk(de->rec_len);
1954                 de = ext3_next_entry(de);
1955         }
1956         brelse (bh);
1957         return 1;
1958 }
1959
1960 /* ext3_orphan_add() links an unlinked or truncated inode into a list of
1961  * such inodes, starting at the superblock, in case we crash before the
1962  * file is closed/deleted, or in case the inode truncate spans multiple
1963  * transactions and the last transaction is not recovered after a crash.
1964  *
1965  * At filesystem recovery time, we walk this list deleting unlinked
1966  * inodes and truncating linked inodes in ext3_orphan_cleanup().
1967  */
1968 int ext3_orphan_add(handle_t *handle, struct inode *inode)
1969 {
1970         struct super_block *sb = inode->i_sb;
1971         struct ext3_iloc iloc;
1972         int err = 0, rc;
1973
1974         mutex_lock(&EXT3_SB(sb)->s_orphan_lock);
1975         if (!list_empty(&EXT3_I(inode)->i_orphan))
1976                 goto out_unlock;
1977
1978         /* Orphan handling is only valid for files with data blocks
1979          * being truncated, or files being unlinked. */
1980
1981         /* @@@ FIXME: Observation from aviro:
1982          * I think I can trigger J_ASSERT in ext3_orphan_add().  We block
1983          * here (on s_orphan_lock), so race with ext3_link() which might bump
1984          * ->i_nlink. For, say it, character device. Not a regular file,
1985          * not a directory, not a symlink and ->i_nlink > 0.
1986          *
1987          * tytso, 4/25/2009: I'm not sure how that could happen;
1988          * shouldn't the fs core protect us from these sort of
1989          * unlink()/link() races?
1990          */
1991         J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1992                 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
1993
1994         BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access");
1995         err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
1996         if (err)
1997                 goto out_unlock;
1998
1999         err = ext3_reserve_inode_write(handle, inode, &iloc);
2000         if (err)
2001                 goto out_unlock;
2002
2003         /* Insert this inode at the head of the on-disk orphan list... */
2004         NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan);
2005         EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2006         err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
2007         rc = ext3_mark_iloc_dirty(handle, inode, &iloc);
2008         if (!err)
2009                 err = rc;
2010
2011         /* Only add to the head of the in-memory list if all the
2012          * previous operations succeeded.  If the orphan_add is going to
2013          * fail (possibly taking the journal offline), we can't risk
2014          * leaving the inode on the orphan list: stray orphan-list
2015          * entries can cause panics at unmount time.
2016          *
2017          * This is safe: on error we're going to ignore the orphan list
2018          * anyway on the next recovery. */
2019         if (!err)
2020                 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan);
2021
2022         jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
2023         jbd_debug(4, "orphan inode %lu will point to %d\n",
2024                         inode->i_ino, NEXT_ORPHAN(inode));
2025 out_unlock:
2026         mutex_unlock(&EXT3_SB(sb)->s_orphan_lock);
2027         ext3_std_error(inode->i_sb, err);
2028         return err;
2029 }
2030
2031 /*
2032  * ext3_orphan_del() removes an unlinked or truncated inode from the list
2033  * of such inodes stored on disk, because it is finally being cleaned up.
2034  */
2035 int ext3_orphan_del(handle_t *handle, struct inode *inode)
2036 {
2037         struct list_head *prev;
2038         struct ext3_inode_info *ei = EXT3_I(inode);
2039         struct ext3_sb_info *sbi;
2040         unsigned long ino_next;
2041         struct ext3_iloc iloc;
2042         int err = 0;
2043
2044         mutex_lock(&EXT3_SB(inode->i_sb)->s_orphan_lock);
2045         if (list_empty(&ei->i_orphan))
2046                 goto out;
2047
2048         ino_next = NEXT_ORPHAN(inode);
2049         prev = ei->i_orphan.prev;
2050         sbi = EXT3_SB(inode->i_sb);
2051
2052         jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
2053
2054         list_del_init(&ei->i_orphan);
2055
2056         /* If we're on an error path, we may not have a valid
2057          * transaction handle with which to update the orphan list on
2058          * disk, but we still need to remove the inode from the linked
2059          * list in memory. */
2060         if (!handle)
2061                 goto out;
2062
2063         err = ext3_reserve_inode_write(handle, inode, &iloc);
2064         if (err)
2065                 goto out_err;
2066
2067         if (prev == &sbi->s_orphan) {
2068                 jbd_debug(4, "superblock will point to %lu\n", ino_next);
2069                 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2070                 err = ext3_journal_get_write_access(handle, sbi->s_sbh);
2071                 if (err)
2072                         goto out_brelse;
2073                 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
2074                 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
2075         } else {
2076                 struct ext3_iloc iloc2;
2077                 struct inode *i_prev =
2078                         &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode;
2079
2080                 jbd_debug(4, "orphan inode %lu will point to %lu\n",
2081                           i_prev->i_ino, ino_next);
2082                 err = ext3_reserve_inode_write(handle, i_prev, &iloc2);
2083                 if (err)
2084                         goto out_brelse;
2085                 NEXT_ORPHAN(i_prev) = ino_next;
2086                 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2);
2087         }
2088         if (err)
2089                 goto out_brelse;
2090         NEXT_ORPHAN(inode) = 0;
2091         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
2092
2093 out_err:
2094         ext3_std_error(inode->i_sb, err);
2095 out:
2096         mutex_unlock(&EXT3_SB(inode->i_sb)->s_orphan_lock);
2097         return err;
2098
2099 out_brelse:
2100         brelse(iloc.bh);
2101         goto out_err;
2102 }
2103
2104 static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
2105 {
2106         int retval;
2107         struct inode * inode;
2108         struct buffer_head * bh;
2109         struct ext3_dir_entry_2 * de;
2110         handle_t *handle;
2111
2112         /* Initialize quotas before so that eventual writes go in
2113          * separate transaction */
2114         dquot_initialize(dir);
2115         dquot_initialize(dentry->d_inode);
2116
2117         handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
2118         if (IS_ERR(handle))
2119                 return PTR_ERR(handle);
2120
2121         retval = -ENOENT;
2122         bh = ext3_find_entry(dir, &dentry->d_name, &de);
2123         if (!bh)
2124                 goto end_rmdir;
2125
2126         if (IS_DIRSYNC(dir))
2127                 handle->h_sync = 1;
2128
2129         inode = dentry->d_inode;
2130
2131         retval = -EIO;
2132         if (le32_to_cpu(de->inode) != inode->i_ino)
2133                 goto end_rmdir;
2134
2135         retval = -ENOTEMPTY;
2136         if (!empty_dir (inode))
2137                 goto end_rmdir;
2138
2139         retval = ext3_delete_entry(handle, dir, de, bh);
2140         if (retval)
2141                 goto end_rmdir;
2142         if (inode->i_nlink != 2)
2143                 ext3_warning (inode->i_sb, "ext3_rmdir",
2144                               "empty directory has nlink!=2 (%d)",
2145                               inode->i_nlink);
2146         inode->i_version++;
2147         clear_nlink(inode);
2148         /* There's no need to set i_disksize: the fact that i_nlink is
2149          * zero will ensure that the right thing happens during any
2150          * recovery. */
2151         inode->i_size = 0;
2152         ext3_orphan_add(handle, inode);
2153         inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
2154         ext3_mark_inode_dirty(handle, inode);
2155         drop_nlink(dir);
2156         ext3_update_dx_flag(dir);
2157         ext3_mark_inode_dirty(handle, dir);
2158
2159 end_rmdir:
2160         ext3_journal_stop(handle);
2161         brelse (bh);
2162         return retval;
2163 }
2164
2165 static int ext3_unlink(struct inode * dir, struct dentry *dentry)
2166 {
2167         int retval;
2168         struct inode * inode;
2169         struct buffer_head * bh;
2170         struct ext3_dir_entry_2 * de;
2171         handle_t *handle;
2172
2173         trace_ext3_unlink_enter(dir, dentry);
2174         /* Initialize quotas before so that eventual writes go
2175          * in separate transaction */
2176         dquot_initialize(dir);
2177         dquot_initialize(dentry->d_inode);
2178
2179         handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
2180         if (IS_ERR(handle))
2181                 return PTR_ERR(handle);
2182
2183         if (IS_DIRSYNC(dir))
2184                 handle->h_sync = 1;
2185
2186         retval = -ENOENT;
2187         bh = ext3_find_entry(dir, &dentry->d_name, &de);
2188         if (!bh)
2189                 goto end_unlink;
2190
2191         inode = dentry->d_inode;
2192
2193         retval = -EIO;
2194         if (le32_to_cpu(de->inode) != inode->i_ino)
2195                 goto end_unlink;
2196
2197         if (!inode->i_nlink) {
2198                 ext3_warning (inode->i_sb, "ext3_unlink",
2199                               "Deleting nonexistent file (%lu), %d",
2200                               inode->i_ino, inode->i_nlink);
2201                 set_nlink(inode, 1);
2202         }
2203         retval = ext3_delete_entry(handle, dir, de, bh);
2204         if (retval)
2205                 goto end_unlink;
2206         dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
2207         ext3_update_dx_flag(dir);
2208         ext3_mark_inode_dirty(handle, dir);
2209         drop_nlink(inode);
2210         if (!inode->i_nlink)
2211                 ext3_orphan_add(handle, inode);
2212         inode->i_ctime = dir->i_ctime;
2213         ext3_mark_inode_dirty(handle, inode);
2214         retval = 0;
2215
2216 end_unlink:
2217         ext3_journal_stop(handle);
2218         brelse (bh);
2219         trace_ext3_unlink_exit(dentry, retval);
2220         return retval;
2221 }
2222
2223 static int ext3_symlink (struct inode * dir,
2224                 struct dentry *dentry, const char * symname)
2225 {
2226         handle_t *handle;
2227         struct inode * inode;
2228         int l, err, retries = 0;
2229         int credits;
2230
2231         l = strlen(symname)+1;
2232         if (l > dir->i_sb->s_blocksize)
2233                 return -ENAMETOOLONG;
2234
2235         dquot_initialize(dir);
2236
2237         if (l > EXT3_N_BLOCKS * 4) {
2238                 /*
2239                  * For non-fast symlinks, we just allocate inode and put it on
2240                  * orphan list in the first transaction => we need bitmap,
2241                  * group descriptor, sb, inode block, quota blocks, and
2242                  * possibly selinux xattr blocks.
2243                  */
2244                 credits = 4 + EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2245                           EXT3_XATTR_TRANS_BLOCKS;
2246         } else {
2247                 /*
2248                  * Fast symlink. We have to add entry to directory
2249                  * (EXT3_DATA_TRANS_BLOCKS + EXT3_INDEX_EXTRA_TRANS_BLOCKS),
2250                  * allocate new inode (bitmap, group descriptor, inode block,
2251                  * quota blocks, sb is already counted in previous macros).
2252                  */
2253                 credits = EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
2254                           EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2255                           EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb);
2256         }
2257 retry:
2258         handle = ext3_journal_start(dir, credits);
2259         if (IS_ERR(handle))
2260                 return PTR_ERR(handle);
2261
2262         if (IS_DIRSYNC(dir))
2263                 handle->h_sync = 1;
2264
2265         inode = ext3_new_inode (handle, dir, &dentry->d_name, S_IFLNK|S_IRWXUGO);
2266         err = PTR_ERR(inode);
2267         if (IS_ERR(inode))
2268                 goto out_stop;
2269
2270         if (l > EXT3_N_BLOCKS * 4) {
2271                 inode->i_op = &ext3_symlink_inode_operations;
2272                 ext3_set_aops(inode);
2273                 /*
2274                  * We cannot call page_symlink() with transaction started
2275                  * because it calls into ext3_write_begin() which acquires page
2276                  * lock which ranks below transaction start (and it can also
2277                  * wait for journal commit if we are running out of space). So
2278                  * we have to stop transaction now and restart it when symlink
2279                  * contents is written. 
2280                  *
2281                  * To keep fs consistent in case of crash, we have to put inode
2282                  * to orphan list in the mean time.
2283                  */
2284                 drop_nlink(inode);
2285                 err = ext3_orphan_add(handle, inode);
2286                 ext3_journal_stop(handle);
2287                 if (err)
2288                         goto err_drop_inode;
2289                 err = __page_symlink(inode, symname, l, 1);
2290                 if (err)
2291                         goto err_drop_inode;
2292                 /*
2293                  * Now inode is being linked into dir (EXT3_DATA_TRANS_BLOCKS
2294                  * + EXT3_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
2295                  */
2296                 handle = ext3_journal_start(dir,
2297                                 EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
2298                                 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 1);
2299                 if (IS_ERR(handle)) {
2300                         err = PTR_ERR(handle);
2301                         goto err_drop_inode;
2302                 }
2303                 set_nlink(inode, 1);
2304                 err = ext3_orphan_del(handle, inode);
2305                 if (err) {
2306                         ext3_journal_stop(handle);
2307                         drop_nlink(inode);
2308                         goto err_drop_inode;
2309                 }
2310         } else {
2311                 inode->i_op = &ext3_fast_symlink_inode_operations;
2312                 memcpy((char*)&EXT3_I(inode)->i_data,symname,l);
2313                 inode->i_size = l-1;
2314         }
2315         EXT3_I(inode)->i_disksize = inode->i_size;
2316         err = ext3_add_nondir(handle, dentry, inode);
2317 out_stop:
2318         ext3_journal_stop(handle);
2319         if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
2320                 goto retry;
2321         return err;
2322 err_drop_inode:
2323         unlock_new_inode(inode);
2324         iput(inode);
2325         return err;
2326 }
2327
2328 static int ext3_link (struct dentry * old_dentry,
2329                 struct inode * dir, struct dentry *dentry)
2330 {
2331         handle_t *handle;
2332         struct inode *inode = old_dentry->d_inode;
2333         int err, retries = 0;
2334
2335         if (inode->i_nlink >= EXT3_LINK_MAX)
2336                 return -EMLINK;
2337
2338         dquot_initialize(dir);
2339
2340 retry:
2341         handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
2342                                         EXT3_INDEX_EXTRA_TRANS_BLOCKS + 1);
2343         if (IS_ERR(handle))
2344                 return PTR_ERR(handle);
2345
2346         if (IS_DIRSYNC(dir))
2347                 handle->h_sync = 1;
2348
2349         inode->i_ctime = CURRENT_TIME_SEC;
2350         inc_nlink(inode);
2351         ihold(inode);
2352
2353         err = ext3_add_entry(handle, dentry, inode);
2354         if (!err) {
2355                 ext3_mark_inode_dirty(handle, inode);
2356                 /* this can happen only for tmpfile being
2357                  * linked the first time
2358                  */
2359                 if (inode->i_nlink == 1)
2360                         ext3_orphan_del(handle, inode);
2361                 d_instantiate(dentry, inode);
2362         } else {
2363                 drop_nlink(inode);
2364                 iput(inode);
2365         }
2366         ext3_journal_stop(handle);
2367         if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
2368                 goto retry;
2369         return err;
2370 }
2371
2372 #define PARENT_INO(buffer) \
2373         (ext3_next_entry((struct ext3_dir_entry_2 *)(buffer))->inode)
2374
2375 /*
2376  * Anybody can rename anything with this: the permission checks are left to the
2377  * higher-level routines.
2378  */
2379 static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
2380                            struct inode * new_dir,struct dentry *new_dentry)
2381 {
2382         handle_t *handle;
2383         struct inode * old_inode, * new_inode;
2384         struct buffer_head * old_bh, * new_bh, * dir_bh;
2385         struct ext3_dir_entry_2 * old_de, * new_de;
2386         int retval, flush_file = 0;
2387
2388         dquot_initialize(old_dir);
2389         dquot_initialize(new_dir);
2390
2391         old_bh = new_bh = dir_bh = NULL;
2392
2393         /* Initialize quotas before so that eventual writes go
2394          * in separate transaction */
2395         if (new_dentry->d_inode)
2396                 dquot_initialize(new_dentry->d_inode);
2397         handle = ext3_journal_start(old_dir, 2 *
2398                                         EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) +
2399                                         EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2);
2400         if (IS_ERR(handle))
2401                 return PTR_ERR(handle);
2402
2403         if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
2404                 handle->h_sync = 1;
2405
2406         old_bh = ext3_find_entry(old_dir, &old_dentry->d_name, &old_de);
2407         /*
2408          *  Check for inode number is _not_ due to possible IO errors.
2409          *  We might rmdir the source, keep it as pwd of some process
2410          *  and merrily kill the link to whatever was created under the
2411          *  same name. Goodbye sticky bit ;-<
2412          */
2413         old_inode = old_dentry->d_inode;
2414         retval = -ENOENT;
2415         if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
2416                 goto end_rename;
2417
2418         new_inode = new_dentry->d_inode;
2419         new_bh = ext3_find_entry(new_dir, &new_dentry->d_name, &new_de);
2420         if (new_bh) {
2421                 if (!new_inode) {
2422                         brelse (new_bh);
2423                         new_bh = NULL;
2424                 }
2425         }
2426         if (S_ISDIR(old_inode->i_mode)) {
2427                 if (new_inode) {
2428                         retval = -ENOTEMPTY;
2429                         if (!empty_dir (new_inode))
2430                                 goto end_rename;
2431                 }
2432                 retval = -EIO;
2433                 dir_bh = ext3_dir_bread(handle, old_inode, 0, 0, &retval);
2434                 if (!dir_bh)
2435                         goto end_rename;
2436                 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
2437                         goto end_rename;
2438                 retval = -EMLINK;
2439                 if (!new_inode && new_dir!=old_dir &&
2440                                 new_dir->i_nlink >= EXT3_LINK_MAX)
2441                         goto end_rename;
2442         }
2443         if (!new_bh) {
2444                 retval = ext3_add_entry (handle, new_dentry, old_inode);
2445                 if (retval)
2446                         goto end_rename;
2447         } else {
2448                 BUFFER_TRACE(new_bh, "get write access");
2449                 retval = ext3_journal_get_write_access(handle, new_bh);
2450                 if (retval)
2451                         goto journal_error;
2452                 new_de->inode = cpu_to_le32(old_inode->i_ino);
2453                 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
2454                                               EXT3_FEATURE_INCOMPAT_FILETYPE))
2455                         new_de->file_type = old_de->file_type;
2456                 new_dir->i_version++;
2457                 new_dir->i_ctime = new_dir->i_mtime = CURRENT_TIME_SEC;
2458                 ext3_mark_inode_dirty(handle, new_dir);
2459                 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata");
2460                 retval = ext3_journal_dirty_metadata(handle, new_bh);
2461                 if (retval)
2462                         goto journal_error;
2463                 brelse(new_bh);
2464                 new_bh = NULL;
2465         }
2466
2467         /*
2468          * Like most other Unix systems, set the ctime for inodes on a
2469          * rename.
2470          */
2471         old_inode->i_ctime = CURRENT_TIME_SEC;
2472         ext3_mark_inode_dirty(handle, old_inode);
2473
2474         /*
2475          * ok, that's it
2476          */
2477         if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
2478             old_de->name_len != old_dentry->d_name.len ||
2479             strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
2480             (retval = ext3_delete_entry(handle, old_dir,
2481                                         old_de, old_bh)) == -ENOENT) {
2482                 /* old_de could have moved from under us during htree split, so
2483                  * make sure that we are deleting the right entry.  We might
2484                  * also be pointing to a stale entry in the unused part of
2485                  * old_bh so just checking inum and the name isn't enough. */
2486                 struct buffer_head *old_bh2;
2487                 struct ext3_dir_entry_2 *old_de2;
2488
2489                 old_bh2 = ext3_find_entry(old_dir, &old_dentry->d_name,
2490                                           &old_de2);
2491                 if (old_bh2) {
2492                         retval = ext3_delete_entry(handle, old_dir,
2493                                                    old_de2, old_bh2);
2494                         brelse(old_bh2);
2495                 }
2496         }
2497         if (retval) {
2498                 ext3_warning(old_dir->i_sb, "ext3_rename",
2499                                 "Deleting old file (%lu), %d, error=%d",
2500                                 old_dir->i_ino, old_dir->i_nlink, retval);
2501         }
2502
2503         if (new_inode) {
2504                 drop_nlink(new_inode);
2505                 new_inode->i_ctime = CURRENT_TIME_SEC;
2506         }
2507         old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
2508         ext3_update_dx_flag(old_dir);
2509         if (dir_bh) {
2510                 BUFFER_TRACE(dir_bh, "get_write_access");
2511                 retval = ext3_journal_get_write_access(handle, dir_bh);
2512                 if (retval)
2513                         goto journal_error;
2514                 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
2515                 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata");
2516                 retval = ext3_journal_dirty_metadata(handle, dir_bh);
2517                 if (retval) {
2518 journal_error:
2519                         ext3_std_error(new_dir->i_sb, retval);
2520                         goto end_rename;
2521                 }
2522                 drop_nlink(old_dir);
2523                 if (new_inode) {
2524                         drop_nlink(new_inode);
2525                 } else {
2526                         inc_nlink(new_dir);
2527                         ext3_update_dx_flag(new_dir);
2528                         ext3_mark_inode_dirty(handle, new_dir);
2529                 }
2530         }
2531         ext3_mark_inode_dirty(handle, old_dir);
2532         if (new_inode) {
2533                 ext3_mark_inode_dirty(handle, new_inode);
2534                 if (!new_inode->i_nlink)
2535                         ext3_orphan_add(handle, new_inode);
2536                 if (ext3_should_writeback_data(new_inode))
2537                         flush_file = 1;
2538         }
2539         retval = 0;
2540
2541 end_rename:
2542         brelse (dir_bh);
2543         brelse (old_bh);
2544         brelse (new_bh);
2545         ext3_journal_stop(handle);
2546         if (retval == 0 && flush_file)
2547                 filemap_flush(old_inode->i_mapping);
2548         return retval;
2549 }
2550
2551 /*
2552  * directories can handle most operations...
2553  */
2554 const struct inode_operations ext3_dir_inode_operations = {
2555         .create         = ext3_create,
2556         .lookup         = ext3_lookup,
2557         .link           = ext3_link,
2558         .unlink         = ext3_unlink,
2559         .symlink        = ext3_symlink,
2560         .mkdir          = ext3_mkdir,
2561         .rmdir          = ext3_rmdir,
2562         .mknod          = ext3_mknod,
2563         .tmpfile        = ext3_tmpfile,
2564         .rename         = ext3_rename,
2565         .setattr        = ext3_setattr,
2566 #ifdef CONFIG_EXT3_FS_XATTR
2567         .setxattr       = generic_setxattr,
2568         .getxattr       = generic_getxattr,
2569         .listxattr      = ext3_listxattr,
2570         .removexattr    = generic_removexattr,
2571 #endif
2572         .get_acl        = ext3_get_acl,
2573 };
2574
2575 const struct inode_operations ext3_special_inode_operations = {
2576         .setattr        = ext3_setattr,
2577 #ifdef CONFIG_EXT3_FS_XATTR
2578         .setxattr       = generic_setxattr,
2579         .getxattr       = generic_getxattr,
2580         .listxattr      = ext3_listxattr,
2581         .removexattr    = generic_removexattr,
2582 #endif
2583         .get_acl        = ext3_get_acl,
2584 };