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1/*
2 * linux/fs/ext4/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/fs.h>
28#include <linux/pagemap.h>
29#include <linux/jbd2.h>
30#include <linux/time.h>
31#include <linux/fcntl.h>
32#include <linux/stat.h>
33#include <linux/string.h>
34#include <linux/quotaops.h>
35#include <linux/buffer_head.h>
36#include <linux/bio.h>
37#include "ext4.h"
38#include "ext4_jbd2.h"
39
40#include "xattr.h"
41#include "acl.h"
42
43#include <trace/events/ext4.h>
44/*
45 * define how far ahead to read directories while searching them.
46 */
47#define NAMEI_RA_CHUNKS 2
48#define NAMEI_RA_BLOCKS 4
49#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
50#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
51
52static struct buffer_head *ext4_append(handle_t *handle,
53 struct inode *inode,
54 ext4_lblk_t *block, int *err)
55{
56 struct buffer_head *bh;
57
58 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
59
60 bh = ext4_bread(handle, inode, *block, 1, err);
61 if (bh) {
62 inode->i_size += inode->i_sb->s_blocksize;
63 EXT4_I(inode)->i_disksize = inode->i_size;
64 *err = ext4_journal_get_write_access(handle, bh);
65 if (*err) {
66 brelse(bh);
67 bh = NULL;
68 }
69 }
70 return bh;
71}
72
73#ifndef assert
74#define assert(test) J_ASSERT(test)
75#endif
76
77#ifdef DX_DEBUG
78#define dxtrace(command) command
79#else
80#define dxtrace(command)
81#endif
82
83struct fake_dirent
84{
85 __le32 inode;
86 __le16 rec_len;
87 u8 name_len;
88 u8 file_type;
89};
90
91struct dx_countlimit
92{
93 __le16 limit;
94 __le16 count;
95};
96
97struct dx_entry
98{
99 __le32 hash;
100 __le32 block;
101};
102
103/*
104 * dx_root_info is laid out so that if it should somehow get overlaid by a
105 * dirent the two low bits of the hash version will be zero. Therefore, the
106 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
107 */
108
109struct dx_root
110{
111 struct fake_dirent dot;
112 char dot_name[4];
113 struct fake_dirent dotdot;
114 char dotdot_name[4];
115 struct dx_root_info
116 {
117 __le32 reserved_zero;
118 u8 hash_version;
119 u8 info_length; /* 8 */
120 u8 indirect_levels;
121 u8 unused_flags;
122 }
123 info;
124 struct dx_entry entries[0];
125};
126
127struct dx_node
128{
129 struct fake_dirent fake;
130 struct dx_entry entries[0];
131};
132
133
134struct dx_frame
135{
136 struct buffer_head *bh;
137 struct dx_entry *entries;
138 struct dx_entry *at;
139};
140
141struct dx_map_entry
142{
143 u32 hash;
144 u16 offs;
145 u16 size;
146};
147
148/*
149 * This goes at the end of each htree block.
150 */
151struct dx_tail {
152 u32 dt_reserved;
153 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
154};
155
156static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
157static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
158static inline unsigned dx_get_hash(struct dx_entry *entry);
159static void dx_set_hash(struct dx_entry *entry, unsigned value);
160static unsigned dx_get_count(struct dx_entry *entries);
161static unsigned dx_get_limit(struct dx_entry *entries);
162static void dx_set_count(struct dx_entry *entries, unsigned value);
163static void dx_set_limit(struct dx_entry *entries, unsigned value);
164static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
165static unsigned dx_node_limit(struct inode *dir);
166static struct dx_frame *dx_probe(const struct qstr *d_name,
167 struct inode *dir,
168 struct dx_hash_info *hinfo,
169 struct dx_frame *frame,
170 int *err);
171static void dx_release(struct dx_frame *frames);
172static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
173 struct dx_hash_info *hinfo, struct dx_map_entry map[]);
174static void dx_sort_map(struct dx_map_entry *map, unsigned count);
175static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
176 struct dx_map_entry *offsets, int count, unsigned blocksize);
177static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
178static void dx_insert_block(struct dx_frame *frame,
179 u32 hash, ext4_lblk_t block);
180static int ext4_htree_next_block(struct inode *dir, __u32 hash,
181 struct dx_frame *frame,
182 struct dx_frame *frames,
183 __u32 *start_hash);
184static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
185 const struct qstr *d_name,
186 struct ext4_dir_entry_2 **res_dir,
187 int *err);
188static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
189 struct inode *inode);
190
191/* checksumming functions */
192#define EXT4_DIRENT_TAIL(block, blocksize) \
193 ((struct ext4_dir_entry_tail *)(((void *)(block)) + \
194 ((blocksize) - \
195 sizeof(struct ext4_dir_entry_tail))))
196
197static void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
198 unsigned int blocksize)
199{
200 memset(t, 0, sizeof(struct ext4_dir_entry_tail));
201 t->det_rec_len = ext4_rec_len_to_disk(
202 sizeof(struct ext4_dir_entry_tail), blocksize);
203 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
204}
205
206/* Walk through a dirent block to find a checksum "dirent" at the tail */
207static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
208 struct ext4_dir_entry *de)
209{
210 struct ext4_dir_entry_tail *t;
211
212#ifdef PARANOID
213 struct ext4_dir_entry *d, *top;
214
215 d = de;
216 top = (struct ext4_dir_entry *)(((void *)de) +
217 (EXT4_BLOCK_SIZE(inode->i_sb) -
218 sizeof(struct ext4_dir_entry_tail)));
219 while (d < top && d->rec_len)
220 d = (struct ext4_dir_entry *)(((void *)d) +
221 le16_to_cpu(d->rec_len));
222
223 if (d != top)
224 return NULL;
225
226 t = (struct ext4_dir_entry_tail *)d;
227#else
228 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
229#endif
230
231 if (t->det_reserved_zero1 ||
232 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
233 t->det_reserved_zero2 ||
234 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
235 return NULL;
236
237 return t;
238}
239
240static __le32 ext4_dirent_csum(struct inode *inode,
241 struct ext4_dir_entry *dirent, int size)
242{
243 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
244 struct ext4_inode_info *ei = EXT4_I(inode);
245 __u32 csum;
246
247 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
248 return cpu_to_le32(csum);
249}
250
251int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
252{
253 struct ext4_dir_entry_tail *t;
254
255 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
256 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
257 return 1;
258
259 t = get_dirent_tail(inode, dirent);
260 if (!t) {
261 EXT4_ERROR_INODE(inode, "metadata_csum set but no space in dir "
262 "leaf for checksum. Please run e2fsck -D.");
263 return 0;
264 }
265
266 if (t->det_checksum != ext4_dirent_csum(inode, dirent,
267 (void *)t - (void *)dirent))
268 return 0;
269
270 return 1;
271}
272
273static void ext4_dirent_csum_set(struct inode *inode,
274 struct ext4_dir_entry *dirent)
275{
276 struct ext4_dir_entry_tail *t;
277
278 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
279 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
280 return;
281
282 t = get_dirent_tail(inode, dirent);
283 if (!t) {
284 EXT4_ERROR_INODE(inode, "metadata_csum set but no space in dir "
285 "leaf for checksum. Please run e2fsck -D.");
286 return;
287 }
288
289 t->det_checksum = ext4_dirent_csum(inode, dirent,
290 (void *)t - (void *)dirent);
291}
292
293static inline int ext4_handle_dirty_dirent_node(handle_t *handle,
294 struct inode *inode,
295 struct buffer_head *bh)
296{
297 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
298 return ext4_handle_dirty_metadata(handle, inode, bh);
299}
300
301static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
302 struct ext4_dir_entry *dirent,
303 int *offset)
304{
305 struct ext4_dir_entry *dp;
306 struct dx_root_info *root;
307 int count_offset;
308
309 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
310 count_offset = 8;
311 else if (le16_to_cpu(dirent->rec_len) == 12) {
312 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
313 if (le16_to_cpu(dp->rec_len) !=
314 EXT4_BLOCK_SIZE(inode->i_sb) - 12)
315 return NULL;
316 root = (struct dx_root_info *)(((void *)dp + 12));
317 if (root->reserved_zero ||
318 root->info_length != sizeof(struct dx_root_info))
319 return NULL;
320 count_offset = 32;
321 } else
322 return NULL;
323
324 if (offset)
325 *offset = count_offset;
326 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
327}
328
329static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
330 int count_offset, int count, struct dx_tail *t)
331{
332 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
333 struct ext4_inode_info *ei = EXT4_I(inode);
334 __u32 csum, old_csum;
335 int size;
336
337 size = count_offset + (count * sizeof(struct dx_entry));
338 old_csum = t->dt_checksum;
339 t->dt_checksum = 0;
340 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
341 csum = ext4_chksum(sbi, csum, (__u8 *)t, sizeof(struct dx_tail));
342 t->dt_checksum = old_csum;
343
344 return cpu_to_le32(csum);
345}
346
347static int ext4_dx_csum_verify(struct inode *inode,
348 struct ext4_dir_entry *dirent)
349{
350 struct dx_countlimit *c;
351 struct dx_tail *t;
352 int count_offset, limit, count;
353
354 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
355 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
356 return 1;
357
358 c = get_dx_countlimit(inode, dirent, &count_offset);
359 if (!c) {
360 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
361 return 1;
362 }
363 limit = le16_to_cpu(c->limit);
364 count = le16_to_cpu(c->count);
365 if (count_offset + (limit * sizeof(struct dx_entry)) >
366 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
367 EXT4_ERROR_INODE(inode, "metadata_csum set but no space for "
368 "tree checksum found. Run e2fsck -D.");
369 return 1;
370 }
371 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
372
373 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
374 count, t))
375 return 0;
376 return 1;
377}
378
379static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
380{
381 struct dx_countlimit *c;
382 struct dx_tail *t;
383 int count_offset, limit, count;
384
385 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
386 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
387 return;
388
389 c = get_dx_countlimit(inode, dirent, &count_offset);
390 if (!c) {
391 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
392 return;
393 }
394 limit = le16_to_cpu(c->limit);
395 count = le16_to_cpu(c->count);
396 if (count_offset + (limit * sizeof(struct dx_entry)) >
397 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
398 EXT4_ERROR_INODE(inode, "metadata_csum set but no space for "
399 "tree checksum. Run e2fsck -D.");
400 return;
401 }
402 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
403
404 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
405}
406
407static inline int ext4_handle_dirty_dx_node(handle_t *handle,
408 struct inode *inode,
409 struct buffer_head *bh)
410{
411 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
412 return ext4_handle_dirty_metadata(handle, inode, bh);
413}
414
415/*
416 * p is at least 6 bytes before the end of page
417 */
418static inline struct ext4_dir_entry_2 *
419ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
420{
421 return (struct ext4_dir_entry_2 *)((char *)p +
422 ext4_rec_len_from_disk(p->rec_len, blocksize));
423}
424
425/*
426 * Future: use high four bits of block for coalesce-on-delete flags
427 * Mask them off for now.
428 */
429
430static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
431{
432 return le32_to_cpu(entry->block) & 0x00ffffff;
433}
434
435static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
436{
437 entry->block = cpu_to_le32(value);
438}
439
440static inline unsigned dx_get_hash(struct dx_entry *entry)
441{
442 return le32_to_cpu(entry->hash);
443}
444
445static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
446{
447 entry->hash = cpu_to_le32(value);
448}
449
450static inline unsigned dx_get_count(struct dx_entry *entries)
451{
452 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
453}
454
455static inline unsigned dx_get_limit(struct dx_entry *entries)
456{
457 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
458}
459
460static inline void dx_set_count(struct dx_entry *entries, unsigned value)
461{
462 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
463}
464
465static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
466{
467 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
468}
469
470static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
471{
472 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
473 EXT4_DIR_REC_LEN(2) - infosize;
474
475 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
476 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
477 entry_space -= sizeof(struct dx_tail);
478 return entry_space / sizeof(struct dx_entry);
479}
480
481static inline unsigned dx_node_limit(struct inode *dir)
482{
483 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
484
485 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
486 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
487 entry_space -= sizeof(struct dx_tail);
488 return entry_space / sizeof(struct dx_entry);
489}
490
491/*
492 * Debug
493 */
494#ifdef DX_DEBUG
495static void dx_show_index(char * label, struct dx_entry *entries)
496{
497 int i, n = dx_get_count (entries);
498 printk(KERN_DEBUG "%s index ", label);
499 for (i = 0; i < n; i++) {
500 printk("%x->%lu ", i ? dx_get_hash(entries + i) :
501 0, (unsigned long)dx_get_block(entries + i));
502 }
503 printk("\n");
504}
505
506struct stats
507{
508 unsigned names;
509 unsigned space;
510 unsigned bcount;
511};
512
513static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
514 int size, int show_names)
515{
516 unsigned names = 0, space = 0;
517 char *base = (char *) de;
518 struct dx_hash_info h = *hinfo;
519
520 printk("names: ");
521 while ((char *) de < base + size)
522 {
523 if (de->inode)
524 {
525 if (show_names)
526 {
527 int len = de->name_len;
528 char *name = de->name;
529 while (len--) printk("%c", *name++);
530 ext4fs_dirhash(de->name, de->name_len, &h);
531 printk(":%x.%u ", h.hash,
532 (unsigned) ((char *) de - base));
533 }
534 space += EXT4_DIR_REC_LEN(de->name_len);
535 names++;
536 }
537 de = ext4_next_entry(de, size);
538 }
539 printk("(%i)\n", names);
540 return (struct stats) { names, space, 1 };
541}
542
543struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
544 struct dx_entry *entries, int levels)
545{
546 unsigned blocksize = dir->i_sb->s_blocksize;
547 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
548 unsigned bcount = 0;
549 struct buffer_head *bh;
550 int err;
551 printk("%i indexed blocks...\n", count);
552 for (i = 0; i < count; i++, entries++)
553 {
554 ext4_lblk_t block = dx_get_block(entries);
555 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
556 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
557 struct stats stats;
558 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
559 if (!(bh = ext4_bread (NULL,dir, block, 0,&err))) continue;
560 stats = levels?
561 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
562 dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
563 names += stats.names;
564 space += stats.space;
565 bcount += stats.bcount;
566 brelse(bh);
567 }
568 if (bcount)
569 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
570 levels ? "" : " ", names, space/bcount,
571 (space/bcount)*100/blocksize);
572 return (struct stats) { names, space, bcount};
573}
574#endif /* DX_DEBUG */
575
576/*
577 * Probe for a directory leaf block to search.
578 *
579 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
580 * error in the directory index, and the caller should fall back to
581 * searching the directory normally. The callers of dx_probe **MUST**
582 * check for this error code, and make sure it never gets reflected
583 * back to userspace.
584 */
585static struct dx_frame *
586dx_probe(const struct qstr *d_name, struct inode *dir,
587 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
588{
589 unsigned count, indirect;
590 struct dx_entry *at, *entries, *p, *q, *m;
591 struct dx_root *root;
592 struct buffer_head *bh;
593 struct dx_frame *frame = frame_in;
594 u32 hash;
595
596 frame->bh = NULL;
597 if (!(bh = ext4_bread (NULL,dir, 0, 0, err)))
598 goto fail;
599 root = (struct dx_root *) bh->b_data;
600 if (root->info.hash_version != DX_HASH_TEA &&
601 root->info.hash_version != DX_HASH_HALF_MD4 &&
602 root->info.hash_version != DX_HASH_LEGACY) {
603 ext4_warning(dir->i_sb, "Unrecognised inode hash code %d",
604 root->info.hash_version);
605 brelse(bh);
606 *err = ERR_BAD_DX_DIR;
607 goto fail;
608 }
609 hinfo->hash_version = root->info.hash_version;
610 if (hinfo->hash_version <= DX_HASH_TEA)
611 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
612 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
613 if (d_name)
614 ext4fs_dirhash(d_name->name, d_name->len, hinfo);
615 hash = hinfo->hash;
616
617 if (root->info.unused_flags & 1) {
618 ext4_warning(dir->i_sb, "Unimplemented inode hash flags: %#06x",
619 root->info.unused_flags);
620 brelse(bh);
621 *err = ERR_BAD_DX_DIR;
622 goto fail;
623 }
624
625 if ((indirect = root->info.indirect_levels) > 1) {
626 ext4_warning(dir->i_sb, "Unimplemented inode hash depth: %#06x",
627 root->info.indirect_levels);
628 brelse(bh);
629 *err = ERR_BAD_DX_DIR;
630 goto fail;
631 }
632
633 if (!buffer_verified(bh) &&
634 !ext4_dx_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data)) {
635 ext4_warning(dir->i_sb, "Root failed checksum");
636 brelse(bh);
637 *err = ERR_BAD_DX_DIR;
638 goto fail;
639 }
640 set_buffer_verified(bh);
641
642 entries = (struct dx_entry *) (((char *)&root->info) +
643 root->info.info_length);
644
645 if (dx_get_limit(entries) != dx_root_limit(dir,
646 root->info.info_length)) {
647 ext4_warning(dir->i_sb, "dx entry: limit != root limit");
648 brelse(bh);
649 *err = ERR_BAD_DX_DIR;
650 goto fail;
651 }
652
653 dxtrace(printk("Look up %x", hash));
654 while (1)
655 {
656 count = dx_get_count(entries);
657 if (!count || count > dx_get_limit(entries)) {
658 ext4_warning(dir->i_sb,
659 "dx entry: no count or count > limit");
660 brelse(bh);
661 *err = ERR_BAD_DX_DIR;
662 goto fail2;
663 }
664
665 p = entries + 1;
666 q = entries + count - 1;
667 while (p <= q)
668 {
669 m = p + (q - p)/2;
670 dxtrace(printk("."));
671 if (dx_get_hash(m) > hash)
672 q = m - 1;
673 else
674 p = m + 1;
675 }
676
677 if (0) // linear search cross check
678 {
679 unsigned n = count - 1;
680 at = entries;
681 while (n--)
682 {
683 dxtrace(printk(","));
684 if (dx_get_hash(++at) > hash)
685 {
686 at--;
687 break;
688 }
689 }
690 assert (at == p - 1);
691 }
692
693 at = p - 1;
694 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
695 frame->bh = bh;
696 frame->entries = entries;
697 frame->at = at;
698 if (!indirect--) return frame;
699 if (!(bh = ext4_bread (NULL,dir, dx_get_block(at), 0, err)))
700 goto fail2;
701 at = entries = ((struct dx_node *) bh->b_data)->entries;
702
703 if (!buffer_verified(bh) &&
704 !ext4_dx_csum_verify(dir,
705 (struct ext4_dir_entry *)bh->b_data)) {
706 ext4_warning(dir->i_sb, "Node failed checksum");
707 brelse(bh);
708 *err = ERR_BAD_DX_DIR;
709 goto fail;
710 }
711 set_buffer_verified(bh);
712
713 if (dx_get_limit(entries) != dx_node_limit (dir)) {
714 ext4_warning(dir->i_sb,
715 "dx entry: limit != node limit");
716 brelse(bh);
717 *err = ERR_BAD_DX_DIR;
718 goto fail2;
719 }
720 frame++;
721 frame->bh = NULL;
722 }
723fail2:
724 while (frame >= frame_in) {
725 brelse(frame->bh);
726 frame--;
727 }
728fail:
729 if (*err == ERR_BAD_DX_DIR)
730 ext4_warning(dir->i_sb,
731 "Corrupt dir inode %lu, running e2fsck is "
732 "recommended.", dir->i_ino);
733 return NULL;
734}
735
736static void dx_release (struct dx_frame *frames)
737{
738 if (frames[0].bh == NULL)
739 return;
740
741 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
742 brelse(frames[1].bh);
743 brelse(frames[0].bh);
744}
745
746/*
747 * This function increments the frame pointer to search the next leaf
748 * block, and reads in the necessary intervening nodes if the search
749 * should be necessary. Whether or not the search is necessary is
750 * controlled by the hash parameter. If the hash value is even, then
751 * the search is only continued if the next block starts with that
752 * hash value. This is used if we are searching for a specific file.
753 *
754 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
755 *
756 * This function returns 1 if the caller should continue to search,
757 * or 0 if it should not. If there is an error reading one of the
758 * index blocks, it will a negative error code.
759 *
760 * If start_hash is non-null, it will be filled in with the starting
761 * hash of the next page.
762 */
763static int ext4_htree_next_block(struct inode *dir, __u32 hash,
764 struct dx_frame *frame,
765 struct dx_frame *frames,
766 __u32 *start_hash)
767{
768 struct dx_frame *p;
769 struct buffer_head *bh;
770 int err, num_frames = 0;
771 __u32 bhash;
772
773 p = frame;
774 /*
775 * Find the next leaf page by incrementing the frame pointer.
776 * If we run out of entries in the interior node, loop around and
777 * increment pointer in the parent node. When we break out of
778 * this loop, num_frames indicates the number of interior
779 * nodes need to be read.
780 */
781 while (1) {
782 if (++(p->at) < p->entries + dx_get_count(p->entries))
783 break;
784 if (p == frames)
785 return 0;
786 num_frames++;
787 p--;
788 }
789
790 /*
791 * If the hash is 1, then continue only if the next page has a
792 * continuation hash of any value. This is used for readdir
793 * handling. Otherwise, check to see if the hash matches the
794 * desired contiuation hash. If it doesn't, return since
795 * there's no point to read in the successive index pages.
796 */
797 bhash = dx_get_hash(p->at);
798 if (start_hash)
799 *start_hash = bhash;
800 if ((hash & 1) == 0) {
801 if ((bhash & ~1) != hash)
802 return 0;
803 }
804 /*
805 * If the hash is HASH_NB_ALWAYS, we always go to the next
806 * block so no check is necessary
807 */
808 while (num_frames--) {
809 if (!(bh = ext4_bread(NULL, dir, dx_get_block(p->at),
810 0, &err)))
811 return err; /* Failure */
812
813 if (!buffer_verified(bh) &&
814 !ext4_dx_csum_verify(dir,
815 (struct ext4_dir_entry *)bh->b_data)) {
816 ext4_warning(dir->i_sb, "Node failed checksum");
817 return -EIO;
818 }
819 set_buffer_verified(bh);
820
821 p++;
822 brelse(p->bh);
823 p->bh = bh;
824 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
825 }
826 return 1;
827}
828
829
830/*
831 * This function fills a red-black tree with information from a
832 * directory block. It returns the number directory entries loaded
833 * into the tree. If there is an error it is returned in err.
834 */
835static int htree_dirblock_to_tree(struct file *dir_file,
836 struct inode *dir, ext4_lblk_t block,
837 struct dx_hash_info *hinfo,
838 __u32 start_hash, __u32 start_minor_hash)
839{
840 struct buffer_head *bh;
841 struct ext4_dir_entry_2 *de, *top;
842 int err, count = 0;
843
844 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
845 (unsigned long)block));
846 if (!(bh = ext4_bread (NULL, dir, block, 0, &err)))
847 return err;
848
849 if (!buffer_verified(bh) &&
850 !ext4_dirent_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data))
851 return -EIO;
852 set_buffer_verified(bh);
853
854 de = (struct ext4_dir_entry_2 *) bh->b_data;
855 top = (struct ext4_dir_entry_2 *) ((char *) de +
856 dir->i_sb->s_blocksize -
857 EXT4_DIR_REC_LEN(0));
858 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
859 if (ext4_check_dir_entry(dir, NULL, de, bh,
860 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
861 + ((char *)de - bh->b_data))) {
862 /* On error, skip the f_pos to the next block. */
863 dir_file->f_pos = (dir_file->f_pos |
864 (dir->i_sb->s_blocksize - 1)) + 1;
865 brelse(bh);
866 return count;
867 }
868 ext4fs_dirhash(de->name, de->name_len, hinfo);
869 if ((hinfo->hash < start_hash) ||
870 ((hinfo->hash == start_hash) &&
871 (hinfo->minor_hash < start_minor_hash)))
872 continue;
873 if (de->inode == 0)
874 continue;
875 if ((err = ext4_htree_store_dirent(dir_file,
876 hinfo->hash, hinfo->minor_hash, de)) != 0) {
877 brelse(bh);
878 return err;
879 }
880 count++;
881 }
882 brelse(bh);
883 return count;
884}
885
886
887/*
888 * This function fills a red-black tree with information from a
889 * directory. We start scanning the directory in hash order, starting
890 * at start_hash and start_minor_hash.
891 *
892 * This function returns the number of entries inserted into the tree,
893 * or a negative error code.
894 */
895int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
896 __u32 start_minor_hash, __u32 *next_hash)
897{
898 struct dx_hash_info hinfo;
899 struct ext4_dir_entry_2 *de;
900 struct dx_frame frames[2], *frame;
901 struct inode *dir;
902 ext4_lblk_t block;
903 int count = 0;
904 int ret, err;
905 __u32 hashval;
906
907 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
908 start_hash, start_minor_hash));
909 dir = dir_file->f_path.dentry->d_inode;
910 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
911 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
912 if (hinfo.hash_version <= DX_HASH_TEA)
913 hinfo.hash_version +=
914 EXT4_SB(dir->i_sb)->s_hash_unsigned;
915 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
916 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
917 start_hash, start_minor_hash);
918 *next_hash = ~0;
919 return count;
920 }
921 hinfo.hash = start_hash;
922 hinfo.minor_hash = 0;
923 frame = dx_probe(NULL, dir, &hinfo, frames, &err);
924 if (!frame)
925 return err;
926
927 /* Add '.' and '..' from the htree header */
928 if (!start_hash && !start_minor_hash) {
929 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
930 if ((err = ext4_htree_store_dirent(dir_file, 0, 0, de)) != 0)
931 goto errout;
932 count++;
933 }
934 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
935 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
936 de = ext4_next_entry(de, dir->i_sb->s_blocksize);
937 if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
938 goto errout;
939 count++;
940 }
941
942 while (1) {
943 block = dx_get_block(frame->at);
944 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
945 start_hash, start_minor_hash);
946 if (ret < 0) {
947 err = ret;
948 goto errout;
949 }
950 count += ret;
951 hashval = ~0;
952 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
953 frame, frames, &hashval);
954 *next_hash = hashval;
955 if (ret < 0) {
956 err = ret;
957 goto errout;
958 }
959 /*
960 * Stop if: (a) there are no more entries, or
961 * (b) we have inserted at least one entry and the
962 * next hash value is not a continuation
963 */
964 if ((ret == 0) ||
965 (count && ((hashval & 1) == 0)))
966 break;
967 }
968 dx_release(frames);
969 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
970 "next hash: %x\n", count, *next_hash));
971 return count;
972errout:
973 dx_release(frames);
974 return (err);
975}
976
977
978/*
979 * Directory block splitting, compacting
980 */
981
982/*
983 * Create map of hash values, offsets, and sizes, stored at end of block.
984 * Returns number of entries mapped.
985 */
986static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
987 struct dx_hash_info *hinfo,
988 struct dx_map_entry *map_tail)
989{
990 int count = 0;
991 char *base = (char *) de;
992 struct dx_hash_info h = *hinfo;
993
994 while ((char *) de < base + blocksize) {
995 if (de->name_len && de->inode) {
996 ext4fs_dirhash(de->name, de->name_len, &h);
997 map_tail--;
998 map_tail->hash = h.hash;
999 map_tail->offs = ((char *) de - base)>>2;
1000 map_tail->size = le16_to_cpu(de->rec_len);
1001 count++;
1002 cond_resched();
1003 }
1004 /* XXX: do we need to check rec_len == 0 case? -Chris */
1005 de = ext4_next_entry(de, blocksize);
1006 }
1007 return count;
1008}
1009
1010/* Sort map by hash value */
1011static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1012{
1013 struct dx_map_entry *p, *q, *top = map + count - 1;
1014 int more;
1015 /* Combsort until bubble sort doesn't suck */
1016 while (count > 2) {
1017 count = count*10/13;
1018 if (count - 9 < 2) /* 9, 10 -> 11 */
1019 count = 11;
1020 for (p = top, q = p - count; q >= map; p--, q--)
1021 if (p->hash < q->hash)
1022 swap(*p, *q);
1023 }
1024 /* Garden variety bubble sort */
1025 do {
1026 more = 0;
1027 q = top;
1028 while (q-- > map) {
1029 if (q[1].hash >= q[0].hash)
1030 continue;
1031 swap(*(q+1), *q);
1032 more = 1;
1033 }
1034 } while(more);
1035}
1036
1037static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
1038{
1039 struct dx_entry *entries = frame->entries;
1040 struct dx_entry *old = frame->at, *new = old + 1;
1041 int count = dx_get_count(entries);
1042
1043 assert(count < dx_get_limit(entries));
1044 assert(old < entries + count);
1045 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1046 dx_set_hash(new, hash);
1047 dx_set_block(new, block);
1048 dx_set_count(entries, count + 1);
1049}
1050
1051static void ext4_update_dx_flag(struct inode *inode)
1052{
1053 if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
1054 EXT4_FEATURE_COMPAT_DIR_INDEX))
1055 ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
1056}
1057
1058/*
1059 * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
1060 *
1061 * `len <= EXT4_NAME_LEN' is guaranteed by caller.
1062 * `de != NULL' is guaranteed by caller.
1063 */
1064static inline int ext4_match (int len, const char * const name,
1065 struct ext4_dir_entry_2 * de)
1066{
1067 if (len != de->name_len)
1068 return 0;
1069 if (!de->inode)
1070 return 0;
1071 return !memcmp(name, de->name, len);
1072}
1073
1074/*
1075 * Returns 0 if not found, -1 on failure, and 1 on success
1076 */
1077static inline int search_dirblock(struct buffer_head *bh,
1078 struct inode *dir,
1079 const struct qstr *d_name,
1080 unsigned int offset,
1081 struct ext4_dir_entry_2 ** res_dir)
1082{
1083 struct ext4_dir_entry_2 * de;
1084 char * dlimit;
1085 int de_len;
1086 const char *name = d_name->name;
1087 int namelen = d_name->len;
1088
1089 de = (struct ext4_dir_entry_2 *) bh->b_data;
1090 dlimit = bh->b_data + dir->i_sb->s_blocksize;
1091 while ((char *) de < dlimit) {
1092 /* this code is executed quadratically often */
1093 /* do minimal checking `by hand' */
1094
1095 if ((char *) de + namelen <= dlimit &&
1096 ext4_match (namelen, name, de)) {
1097 /* found a match - just to be sure, do a full check */
1098 if (ext4_check_dir_entry(dir, NULL, de, bh, offset))
1099 return -1;
1100 *res_dir = de;
1101 return 1;
1102 }
1103 /* prevent looping on a bad block */
1104 de_len = ext4_rec_len_from_disk(de->rec_len,
1105 dir->i_sb->s_blocksize);
1106 if (de_len <= 0)
1107 return -1;
1108 offset += de_len;
1109 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1110 }
1111 return 0;
1112}
1113
1114
1115/*
1116 * ext4_find_entry()
1117 *
1118 * finds an entry in the specified directory with the wanted name. It
1119 * returns the cache buffer in which the entry was found, and the entry
1120 * itself (as a parameter - res_dir). It does NOT read the inode of the
1121 * entry - you'll have to do that yourself if you want to.
1122 *
1123 * The returned buffer_head has ->b_count elevated. The caller is expected
1124 * to brelse() it when appropriate.
1125 */
1126static struct buffer_head * ext4_find_entry (struct inode *dir,
1127 const struct qstr *d_name,
1128 struct ext4_dir_entry_2 ** res_dir)
1129{
1130 struct super_block *sb;
1131 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1132 struct buffer_head *bh, *ret = NULL;
1133 ext4_lblk_t start, block, b;
1134 const u8 *name = d_name->name;
1135 int ra_max = 0; /* Number of bh's in the readahead
1136 buffer, bh_use[] */
1137 int ra_ptr = 0; /* Current index into readahead
1138 buffer */
1139 int num = 0;
1140 ext4_lblk_t nblocks;
1141 int i, err;
1142 int namelen;
1143
1144 *res_dir = NULL;
1145 sb = dir->i_sb;
1146 namelen = d_name->len;
1147 if (namelen > EXT4_NAME_LEN)
1148 return NULL;
1149 if ((namelen <= 2) && (name[0] == '.') &&
1150 (name[1] == '.' || name[1] == '\0')) {
1151 /*
1152 * "." or ".." will only be in the first block
1153 * NFS may look up ".."; "." should be handled by the VFS
1154 */
1155 block = start = 0;
1156 nblocks = 1;
1157 goto restart;
1158 }
1159 if (is_dx(dir)) {
1160 bh = ext4_dx_find_entry(dir, d_name, res_dir, &err);
1161 /*
1162 * On success, or if the error was file not found,
1163 * return. Otherwise, fall back to doing a search the
1164 * old fashioned way.
1165 */
1166 if (bh || (err != ERR_BAD_DX_DIR))
1167 return bh;
1168 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1169 "falling back\n"));
1170 }
1171 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1172 start = EXT4_I(dir)->i_dir_start_lookup;
1173 if (start >= nblocks)
1174 start = 0;
1175 block = start;
1176restart:
1177 do {
1178 /*
1179 * We deal with the read-ahead logic here.
1180 */
1181 if (ra_ptr >= ra_max) {
1182 /* Refill the readahead buffer */
1183 ra_ptr = 0;
1184 b = block;
1185 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
1186 /*
1187 * Terminate if we reach the end of the
1188 * directory and must wrap, or if our
1189 * search has finished at this block.
1190 */
1191 if (b >= nblocks || (num && block == start)) {
1192 bh_use[ra_max] = NULL;
1193 break;
1194 }
1195 num++;
1196 bh = ext4_getblk(NULL, dir, b++, 0, &err);
1197 bh_use[ra_max] = bh;
1198 if (bh)
1199 ll_rw_block(READ | REQ_META | REQ_PRIO,
1200 1, &bh);
1201 }
1202 }
1203 if ((bh = bh_use[ra_ptr++]) == NULL)
1204 goto next;
1205 wait_on_buffer(bh);
1206 if (!buffer_uptodate(bh)) {
1207 /* read error, skip block & hope for the best */
1208 EXT4_ERROR_INODE(dir, "reading directory lblock %lu",
1209 (unsigned long) block);
1210 brelse(bh);
1211 goto next;
1212 }
1213 if (!buffer_verified(bh) &&
1214 !ext4_dirent_csum_verify(dir,
1215 (struct ext4_dir_entry *)bh->b_data)) {
1216 EXT4_ERROR_INODE(dir, "checksumming directory "
1217 "block %lu", (unsigned long)block);
1218 brelse(bh);
1219 goto next;
1220 }
1221 set_buffer_verified(bh);
1222 i = search_dirblock(bh, dir, d_name,
1223 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
1224 if (i == 1) {
1225 EXT4_I(dir)->i_dir_start_lookup = block;
1226 ret = bh;
1227 goto cleanup_and_exit;
1228 } else {
1229 brelse(bh);
1230 if (i < 0)
1231 goto cleanup_and_exit;
1232 }
1233 next:
1234 if (++block >= nblocks)
1235 block = 0;
1236 } while (block != start);
1237
1238 /*
1239 * If the directory has grown while we were searching, then
1240 * search the last part of the directory before giving up.
1241 */
1242 block = nblocks;
1243 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1244 if (block < nblocks) {
1245 start = 0;
1246 goto restart;
1247 }
1248
1249cleanup_and_exit:
1250 /* Clean up the read-ahead blocks */
1251 for (; ra_ptr < ra_max; ra_ptr++)
1252 brelse(bh_use[ra_ptr]);
1253 return ret;
1254}
1255
1256static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct qstr *d_name,
1257 struct ext4_dir_entry_2 **res_dir, int *err)
1258{
1259 struct super_block * sb = dir->i_sb;
1260 struct dx_hash_info hinfo;
1261 struct dx_frame frames[2], *frame;
1262 struct buffer_head *bh;
1263 ext4_lblk_t block;
1264 int retval;
1265
1266 if (!(frame = dx_probe(d_name, dir, &hinfo, frames, err)))
1267 return NULL;
1268 do {
1269 block = dx_get_block(frame->at);
1270 if (!(bh = ext4_bread(NULL, dir, block, 0, err)))
1271 goto errout;
1272
1273 if (!buffer_verified(bh) &&
1274 !ext4_dirent_csum_verify(dir,
1275 (struct ext4_dir_entry *)bh->b_data)) {
1276 EXT4_ERROR_INODE(dir, "checksumming directory "
1277 "block %lu", (unsigned long)block);
1278 brelse(bh);
1279 *err = -EIO;
1280 goto errout;
1281 }
1282 set_buffer_verified(bh);
1283 retval = search_dirblock(bh, dir, d_name,
1284 block << EXT4_BLOCK_SIZE_BITS(sb),
1285 res_dir);
1286 if (retval == 1) { /* Success! */
1287 dx_release(frames);
1288 return bh;
1289 }
1290 brelse(bh);
1291 if (retval == -1) {
1292 *err = ERR_BAD_DX_DIR;
1293 goto errout;
1294 }
1295
1296 /* Check to see if we should continue to search */
1297 retval = ext4_htree_next_block(dir, hinfo.hash, frame,
1298 frames, NULL);
1299 if (retval < 0) {
1300 ext4_warning(sb,
1301 "error reading index page in directory #%lu",
1302 dir->i_ino);
1303 *err = retval;
1304 goto errout;
1305 }
1306 } while (retval == 1);
1307
1308 *err = -ENOENT;
1309errout:
1310 dxtrace(printk(KERN_DEBUG "%s not found\n", d_name->name));
1311 dx_release (frames);
1312 return NULL;
1313}
1314
1315static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
1316{
1317 struct inode *inode;
1318 struct ext4_dir_entry_2 *de;
1319 struct buffer_head *bh;
1320
1321 if (dentry->d_name.len > EXT4_NAME_LEN)
1322 return ERR_PTR(-ENAMETOOLONG);
1323
1324 bh = ext4_find_entry(dir, &dentry->d_name, &de);
1325 inode = NULL;
1326 if (bh) {
1327 __u32 ino = le32_to_cpu(de->inode);
1328 brelse(bh);
1329 if (!ext4_valid_inum(dir->i_sb, ino)) {
1330 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1331 return ERR_PTR(-EIO);
1332 }
1333 if (unlikely(ino == dir->i_ino)) {
1334 EXT4_ERROR_INODE(dir, "'%.*s' linked to parent dir",
1335 dentry->d_name.len,
1336 dentry->d_name.name);
1337 return ERR_PTR(-EIO);
1338 }
1339 inode = ext4_iget(dir->i_sb, ino);
1340 if (inode == ERR_PTR(-ESTALE)) {
1341 EXT4_ERROR_INODE(dir,
1342 "deleted inode referenced: %u",
1343 ino);
1344 return ERR_PTR(-EIO);
1345 }
1346 }
1347 return d_splice_alias(inode, dentry);
1348}
1349
1350
1351struct dentry *ext4_get_parent(struct dentry *child)
1352{
1353 __u32 ino;
1354 static const struct qstr dotdot = QSTR_INIT("..", 2);
1355 struct ext4_dir_entry_2 * de;
1356 struct buffer_head *bh;
1357
1358 bh = ext4_find_entry(child->d_inode, &dotdot, &de);
1359 if (!bh)
1360 return ERR_PTR(-ENOENT);
1361 ino = le32_to_cpu(de->inode);
1362 brelse(bh);
1363
1364 if (!ext4_valid_inum(child->d_inode->i_sb, ino)) {
1365 EXT4_ERROR_INODE(child->d_inode,
1366 "bad parent inode number: %u", ino);
1367 return ERR_PTR(-EIO);
1368 }
1369
1370 return d_obtain_alias(ext4_iget(child->d_inode->i_sb, ino));
1371}
1372
1373#define S_SHIFT 12
1374static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
1375 [S_IFREG >> S_SHIFT] = EXT4_FT_REG_FILE,
1376 [S_IFDIR >> S_SHIFT] = EXT4_FT_DIR,
1377 [S_IFCHR >> S_SHIFT] = EXT4_FT_CHRDEV,
1378 [S_IFBLK >> S_SHIFT] = EXT4_FT_BLKDEV,
1379 [S_IFIFO >> S_SHIFT] = EXT4_FT_FIFO,
1380 [S_IFSOCK >> S_SHIFT] = EXT4_FT_SOCK,
1381 [S_IFLNK >> S_SHIFT] = EXT4_FT_SYMLINK,
1382};
1383
1384static inline void ext4_set_de_type(struct super_block *sb,
1385 struct ext4_dir_entry_2 *de,
1386 umode_t mode) {
1387 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
1388 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
1389}
1390
1391/*
1392 * Move count entries from end of map between two memory locations.
1393 * Returns pointer to last entry moved.
1394 */
1395static struct ext4_dir_entry_2 *
1396dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1397 unsigned blocksize)
1398{
1399 unsigned rec_len = 0;
1400
1401 while (count--) {
1402 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
1403 (from + (map->offs<<2));
1404 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1405 memcpy (to, de, rec_len);
1406 ((struct ext4_dir_entry_2 *) to)->rec_len =
1407 ext4_rec_len_to_disk(rec_len, blocksize);
1408 de->inode = 0;
1409 map++;
1410 to += rec_len;
1411 }
1412 return (struct ext4_dir_entry_2 *) (to - rec_len);
1413}
1414
1415/*
1416 * Compact each dir entry in the range to the minimal rec_len.
1417 * Returns pointer to last entry in range.
1418 */
1419static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
1420{
1421 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
1422 unsigned rec_len = 0;
1423
1424 prev = to = de;
1425 while ((char*)de < base + blocksize) {
1426 next = ext4_next_entry(de, blocksize);
1427 if (de->inode && de->name_len) {
1428 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1429 if (de > to)
1430 memmove(to, de, rec_len);
1431 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
1432 prev = to;
1433 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
1434 }
1435 de = next;
1436 }
1437 return prev;
1438}
1439
1440/*
1441 * Split a full leaf block to make room for a new dir entry.
1442 * Allocate a new block, and move entries so that they are approx. equally full.
1443 * Returns pointer to de in block into which the new entry will be inserted.
1444 */
1445static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1446 struct buffer_head **bh,struct dx_frame *frame,
1447 struct dx_hash_info *hinfo, int *error)
1448{
1449 unsigned blocksize = dir->i_sb->s_blocksize;
1450 unsigned count, continued;
1451 struct buffer_head *bh2;
1452 ext4_lblk_t newblock;
1453 u32 hash2;
1454 struct dx_map_entry *map;
1455 char *data1 = (*bh)->b_data, *data2;
1456 unsigned split, move, size;
1457 struct ext4_dir_entry_2 *de = NULL, *de2;
1458 struct ext4_dir_entry_tail *t;
1459 int csum_size = 0;
1460 int err = 0, i;
1461
1462 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
1463 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1464 csum_size = sizeof(struct ext4_dir_entry_tail);
1465
1466 bh2 = ext4_append (handle, dir, &newblock, &err);
1467 if (!(bh2)) {
1468 brelse(*bh);
1469 *bh = NULL;
1470 goto errout;
1471 }
1472
1473 BUFFER_TRACE(*bh, "get_write_access");
1474 err = ext4_journal_get_write_access(handle, *bh);
1475 if (err)
1476 goto journal_error;
1477
1478 BUFFER_TRACE(frame->bh, "get_write_access");
1479 err = ext4_journal_get_write_access(handle, frame->bh);
1480 if (err)
1481 goto journal_error;
1482
1483 data2 = bh2->b_data;
1484
1485 /* create map in the end of data2 block */
1486 map = (struct dx_map_entry *) (data2 + blocksize);
1487 count = dx_make_map((struct ext4_dir_entry_2 *) data1,
1488 blocksize, hinfo, map);
1489 map -= count;
1490 dx_sort_map(map, count);
1491 /* Split the existing block in the middle, size-wise */
1492 size = 0;
1493 move = 0;
1494 for (i = count-1; i >= 0; i--) {
1495 /* is more than half of this entry in 2nd half of the block? */
1496 if (size + map[i].size/2 > blocksize/2)
1497 break;
1498 size += map[i].size;
1499 move++;
1500 }
1501 /* map index at which we will split */
1502 split = count - move;
1503 hash2 = map[split].hash;
1504 continued = hash2 == map[split - 1].hash;
1505 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1506 (unsigned long)dx_get_block(frame->at),
1507 hash2, split, count-split));
1508
1509 /* Fancy dance to stay within two buffers */
1510 de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize);
1511 de = dx_pack_dirents(data1, blocksize);
1512 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1513 (char *) de,
1514 blocksize);
1515 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1516 (char *) de2,
1517 blocksize);
1518 if (csum_size) {
1519 t = EXT4_DIRENT_TAIL(data2, blocksize);
1520 initialize_dirent_tail(t, blocksize);
1521
1522 t = EXT4_DIRENT_TAIL(data1, blocksize);
1523 initialize_dirent_tail(t, blocksize);
1524 }
1525
1526 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
1527 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
1528
1529 /* Which block gets the new entry? */
1530 if (hinfo->hash >= hash2)
1531 {
1532 swap(*bh, bh2);
1533 de = de2;
1534 }
1535 dx_insert_block(frame, hash2 + continued, newblock);
1536 err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
1537 if (err)
1538 goto journal_error;
1539 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1540 if (err)
1541 goto journal_error;
1542 brelse(bh2);
1543 dxtrace(dx_show_index("frame", frame->entries));
1544 return de;
1545
1546journal_error:
1547 brelse(*bh);
1548 brelse(bh2);
1549 *bh = NULL;
1550 ext4_std_error(dir->i_sb, err);
1551errout:
1552 *error = err;
1553 return NULL;
1554}
1555
1556/*
1557 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1558 * it points to a directory entry which is guaranteed to be large
1559 * enough for new directory entry. If de is NULL, then
1560 * add_dirent_to_buf will attempt search the directory block for
1561 * space. It will return -ENOSPC if no space is available, and -EIO
1562 * and -EEXIST if directory entry already exists.
1563 */
1564static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
1565 struct inode *inode, struct ext4_dir_entry_2 *de,
1566 struct buffer_head *bh)
1567{
1568 struct inode *dir = dentry->d_parent->d_inode;
1569 const char *name = dentry->d_name.name;
1570 int namelen = dentry->d_name.len;
1571 unsigned int offset = 0;
1572 unsigned int blocksize = dir->i_sb->s_blocksize;
1573 unsigned short reclen;
1574 int nlen, rlen, err;
1575 char *top;
1576 int csum_size = 0;
1577
1578 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1579 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1580 csum_size = sizeof(struct ext4_dir_entry_tail);
1581
1582 reclen = EXT4_DIR_REC_LEN(namelen);
1583 if (!de) {
1584 de = (struct ext4_dir_entry_2 *)bh->b_data;
1585 top = bh->b_data + (blocksize - csum_size) - reclen;
1586 while ((char *) de <= top) {
1587 if (ext4_check_dir_entry(dir, NULL, de, bh, offset))
1588 return -EIO;
1589 if (ext4_match(namelen, name, de))
1590 return -EEXIST;
1591 nlen = EXT4_DIR_REC_LEN(de->name_len);
1592 rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
1593 if ((de->inode? rlen - nlen: rlen) >= reclen)
1594 break;
1595 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1596 offset += rlen;
1597 }
1598 if ((char *) de > top)
1599 return -ENOSPC;
1600 }
1601 BUFFER_TRACE(bh, "get_write_access");
1602 err = ext4_journal_get_write_access(handle, bh);
1603 if (err) {
1604 ext4_std_error(dir->i_sb, err);
1605 return err;
1606 }
1607
1608 /* By now the buffer is marked for journaling */
1609 nlen = EXT4_DIR_REC_LEN(de->name_len);
1610 rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
1611 if (de->inode) {
1612 struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen);
1613 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, blocksize);
1614 de->rec_len = ext4_rec_len_to_disk(nlen, blocksize);
1615 de = de1;
1616 }
1617 de->file_type = EXT4_FT_UNKNOWN;
1618 de->inode = cpu_to_le32(inode->i_ino);
1619 ext4_set_de_type(dir->i_sb, de, inode->i_mode);
1620 de->name_len = namelen;
1621 memcpy(de->name, name, namelen);
1622 /*
1623 * XXX shouldn't update any times until successful
1624 * completion of syscall, but too many callers depend
1625 * on this.
1626 *
1627 * XXX similarly, too many callers depend on
1628 * ext4_new_inode() setting the times, but error
1629 * recovery deletes the inode, so the worst that can
1630 * happen is that the times are slightly out of date
1631 * and/or different from the directory change time.
1632 */
1633 dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
1634 ext4_update_dx_flag(dir);
1635 dir->i_version++;
1636 ext4_mark_inode_dirty(handle, dir);
1637 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
1638 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
1639 if (err)
1640 ext4_std_error(dir->i_sb, err);
1641 return 0;
1642}
1643
1644/*
1645 * This converts a one block unindexed directory to a 3 block indexed
1646 * directory, and adds the dentry to the indexed directory.
1647 */
1648static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1649 struct inode *inode, struct buffer_head *bh)
1650{
1651 struct inode *dir = dentry->d_parent->d_inode;
1652 const char *name = dentry->d_name.name;
1653 int namelen = dentry->d_name.len;
1654 struct buffer_head *bh2;
1655 struct dx_root *root;
1656 struct dx_frame frames[2], *frame;
1657 struct dx_entry *entries;
1658 struct ext4_dir_entry_2 *de, *de2;
1659 struct ext4_dir_entry_tail *t;
1660 char *data1, *top;
1661 unsigned len;
1662 int retval;
1663 unsigned blocksize;
1664 struct dx_hash_info hinfo;
1665 ext4_lblk_t block;
1666 struct fake_dirent *fde;
1667 int csum_size = 0;
1668
1669 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1670 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1671 csum_size = sizeof(struct ext4_dir_entry_tail);
1672
1673 blocksize = dir->i_sb->s_blocksize;
1674 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
1675 retval = ext4_journal_get_write_access(handle, bh);
1676 if (retval) {
1677 ext4_std_error(dir->i_sb, retval);
1678 brelse(bh);
1679 return retval;
1680 }
1681 root = (struct dx_root *) bh->b_data;
1682
1683 /* The 0th block becomes the root, move the dirents out */
1684 fde = &root->dotdot;
1685 de = (struct ext4_dir_entry_2 *)((char *)fde +
1686 ext4_rec_len_from_disk(fde->rec_len, blocksize));
1687 if ((char *) de >= (((char *) root) + blocksize)) {
1688 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
1689 brelse(bh);
1690 return -EIO;
1691 }
1692 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
1693
1694 /* Allocate new block for the 0th block's dirents */
1695 bh2 = ext4_append(handle, dir, &block, &retval);
1696 if (!(bh2)) {
1697 brelse(bh);
1698 return retval;
1699 }
1700 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
1701 data1 = bh2->b_data;
1702
1703 memcpy (data1, de, len);
1704 de = (struct ext4_dir_entry_2 *) data1;
1705 top = data1 + len;
1706 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
1707 de = de2;
1708 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1709 (char *) de,
1710 blocksize);
1711
1712 if (csum_size) {
1713 t = EXT4_DIRENT_TAIL(data1, blocksize);
1714 initialize_dirent_tail(t, blocksize);
1715 }
1716
1717 /* Initialize the root; the dot dirents already exist */
1718 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
1719 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
1720 blocksize);
1721 memset (&root->info, 0, sizeof(root->info));
1722 root->info.info_length = sizeof(root->info);
1723 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
1724 entries = root->entries;
1725 dx_set_block(entries, 1);
1726 dx_set_count(entries, 1);
1727 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
1728
1729 /* Initialize as for dx_probe */
1730 hinfo.hash_version = root->info.hash_version;
1731 if (hinfo.hash_version <= DX_HASH_TEA)
1732 hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
1733 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1734 ext4fs_dirhash(name, namelen, &hinfo);
1735 frame = frames;
1736 frame->entries = entries;
1737 frame->at = entries;
1738 frame->bh = bh;
1739 bh = bh2;
1740
1741 ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1742 ext4_handle_dirty_dirent_node(handle, dir, bh);
1743
1744 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
1745 if (!de) {
1746 /*
1747 * Even if the block split failed, we have to properly write
1748 * out all the changes we did so far. Otherwise we can end up
1749 * with corrupted filesystem.
1750 */
1751 ext4_mark_inode_dirty(handle, dir);
1752 dx_release(frames);
1753 return retval;
1754 }
1755 dx_release(frames);
1756
1757 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1758 brelse(bh);
1759 return retval;
1760}
1761
1762/*
1763 * ext4_add_entry()
1764 *
1765 * adds a file entry to the specified directory, using the same
1766 * semantics as ext4_find_entry(). It returns NULL if it failed.
1767 *
1768 * NOTE!! The inode part of 'de' is left at 0 - which means you
1769 * may not sleep between calling this and putting something into
1770 * the entry, as someone else might have used it while you slept.
1771 */
1772static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
1773 struct inode *inode)
1774{
1775 struct inode *dir = dentry->d_parent->d_inode;
1776 struct buffer_head *bh;
1777 struct ext4_dir_entry_2 *de;
1778 struct ext4_dir_entry_tail *t;
1779 struct super_block *sb;
1780 int retval;
1781 int dx_fallback=0;
1782 unsigned blocksize;
1783 ext4_lblk_t block, blocks;
1784 int csum_size = 0;
1785
1786 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1787 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1788 csum_size = sizeof(struct ext4_dir_entry_tail);
1789
1790 sb = dir->i_sb;
1791 blocksize = sb->s_blocksize;
1792 if (!dentry->d_name.len)
1793 return -EINVAL;
1794 if (is_dx(dir)) {
1795 retval = ext4_dx_add_entry(handle, dentry, inode);
1796 if (!retval || (retval != ERR_BAD_DX_DIR))
1797 return retval;
1798 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
1799 dx_fallback++;
1800 ext4_mark_inode_dirty(handle, dir);
1801 }
1802 blocks = dir->i_size >> sb->s_blocksize_bits;
1803 for (block = 0; block < blocks; block++) {
1804 bh = ext4_bread(handle, dir, block, 0, &retval);
1805 if(!bh)
1806 return retval;
1807 if (!buffer_verified(bh) &&
1808 !ext4_dirent_csum_verify(dir,
1809 (struct ext4_dir_entry *)bh->b_data))
1810 return -EIO;
1811 set_buffer_verified(bh);
1812 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1813 if (retval != -ENOSPC) {
1814 brelse(bh);
1815 return retval;
1816 }
1817
1818 if (blocks == 1 && !dx_fallback &&
1819 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
1820 return make_indexed_dir(handle, dentry, inode, bh);
1821 brelse(bh);
1822 }
1823 bh = ext4_append(handle, dir, &block, &retval);
1824 if (!bh)
1825 return retval;
1826 de = (struct ext4_dir_entry_2 *) bh->b_data;
1827 de->inode = 0;
1828 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
1829
1830 if (csum_size) {
1831 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
1832 initialize_dirent_tail(t, blocksize);
1833 }
1834
1835 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1836 brelse(bh);
1837 if (retval == 0)
1838 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
1839 return retval;
1840}
1841
1842/*
1843 * Returns 0 for success, or a negative error value
1844 */
1845static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
1846 struct inode *inode)
1847{
1848 struct dx_frame frames[2], *frame;
1849 struct dx_entry *entries, *at;
1850 struct dx_hash_info hinfo;
1851 struct buffer_head *bh;
1852 struct inode *dir = dentry->d_parent->d_inode;
1853 struct super_block *sb = dir->i_sb;
1854 struct ext4_dir_entry_2 *de;
1855 int err;
1856
1857 frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err);
1858 if (!frame)
1859 return err;
1860 entries = frame->entries;
1861 at = frame->at;
1862
1863 if (!(bh = ext4_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
1864 goto cleanup;
1865
1866 if (!buffer_verified(bh) &&
1867 !ext4_dirent_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data))
1868 goto journal_error;
1869 set_buffer_verified(bh);
1870
1871 BUFFER_TRACE(bh, "get_write_access");
1872 err = ext4_journal_get_write_access(handle, bh);
1873 if (err)
1874 goto journal_error;
1875
1876 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1877 if (err != -ENOSPC)
1878 goto cleanup;
1879
1880 /* Block full, should compress but for now just split */
1881 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
1882 dx_get_count(entries), dx_get_limit(entries)));
1883 /* Need to split index? */
1884 if (dx_get_count(entries) == dx_get_limit(entries)) {
1885 ext4_lblk_t newblock;
1886 unsigned icount = dx_get_count(entries);
1887 int levels = frame - frames;
1888 struct dx_entry *entries2;
1889 struct dx_node *node2;
1890 struct buffer_head *bh2;
1891
1892 if (levels && (dx_get_count(frames->entries) ==
1893 dx_get_limit(frames->entries))) {
1894 ext4_warning(sb, "Directory index full!");
1895 err = -ENOSPC;
1896 goto cleanup;
1897 }
1898 bh2 = ext4_append (handle, dir, &newblock, &err);
1899 if (!(bh2))
1900 goto cleanup;
1901 node2 = (struct dx_node *)(bh2->b_data);
1902 entries2 = node2->entries;
1903 memset(&node2->fake, 0, sizeof(struct fake_dirent));
1904 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
1905 sb->s_blocksize);
1906 BUFFER_TRACE(frame->bh, "get_write_access");
1907 err = ext4_journal_get_write_access(handle, frame->bh);
1908 if (err)
1909 goto journal_error;
1910 if (levels) {
1911 unsigned icount1 = icount/2, icount2 = icount - icount1;
1912 unsigned hash2 = dx_get_hash(entries + icount1);
1913 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
1914 icount1, icount2));
1915
1916 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
1917 err = ext4_journal_get_write_access(handle,
1918 frames[0].bh);
1919 if (err)
1920 goto journal_error;
1921
1922 memcpy((char *) entries2, (char *) (entries + icount1),
1923 icount2 * sizeof(struct dx_entry));
1924 dx_set_count(entries, icount1);
1925 dx_set_count(entries2, icount2);
1926 dx_set_limit(entries2, dx_node_limit(dir));
1927
1928 /* Which index block gets the new entry? */
1929 if (at - entries >= icount1) {
1930 frame->at = at = at - entries - icount1 + entries2;
1931 frame->entries = entries = entries2;
1932 swap(frame->bh, bh2);
1933 }
1934 dx_insert_block(frames + 0, hash2, newblock);
1935 dxtrace(dx_show_index("node", frames[1].entries));
1936 dxtrace(dx_show_index("node",
1937 ((struct dx_node *) bh2->b_data)->entries));
1938 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
1939 if (err)
1940 goto journal_error;
1941 brelse (bh2);
1942 } else {
1943 dxtrace(printk(KERN_DEBUG
1944 "Creating second level index...\n"));
1945 memcpy((char *) entries2, (char *) entries,
1946 icount * sizeof(struct dx_entry));
1947 dx_set_limit(entries2, dx_node_limit(dir));
1948
1949 /* Set up root */
1950 dx_set_count(entries, 1);
1951 dx_set_block(entries + 0, newblock);
1952 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
1953
1954 /* Add new access path frame */
1955 frame = frames + 1;
1956 frame->at = at = at - entries + entries2;
1957 frame->entries = entries = entries2;
1958 frame->bh = bh2;
1959 err = ext4_journal_get_write_access(handle,
1960 frame->bh);
1961 if (err)
1962 goto journal_error;
1963 }
1964 err = ext4_handle_dirty_dx_node(handle, dir, frames[0].bh);
1965 if (err) {
1966 ext4_std_error(inode->i_sb, err);
1967 goto cleanup;
1968 }
1969 }
1970 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
1971 if (!de)
1972 goto cleanup;
1973 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
1974 goto cleanup;
1975
1976journal_error:
1977 ext4_std_error(dir->i_sb, err);
1978cleanup:
1979 if (bh)
1980 brelse(bh);
1981 dx_release(frames);
1982 return err;
1983}
1984
1985/*
1986 * ext4_delete_entry deletes a directory entry by merging it with the
1987 * previous entry
1988 */
1989static int ext4_delete_entry(handle_t *handle,
1990 struct inode *dir,
1991 struct ext4_dir_entry_2 *de_del,
1992 struct buffer_head *bh)
1993{
1994 struct ext4_dir_entry_2 *de, *pde;
1995 unsigned int blocksize = dir->i_sb->s_blocksize;
1996 int csum_size = 0;
1997 int i, err;
1998
1999 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2000 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2001 csum_size = sizeof(struct ext4_dir_entry_tail);
2002
2003 i = 0;
2004 pde = NULL;
2005 de = (struct ext4_dir_entry_2 *) bh->b_data;
2006 while (i < bh->b_size - csum_size) {
2007 if (ext4_check_dir_entry(dir, NULL, de, bh, i))
2008 return -EIO;
2009 if (de == de_del) {
2010 BUFFER_TRACE(bh, "get_write_access");
2011 err = ext4_journal_get_write_access(handle, bh);
2012 if (unlikely(err)) {
2013 ext4_std_error(dir->i_sb, err);
2014 return err;
2015 }
2016 if (pde)
2017 pde->rec_len = ext4_rec_len_to_disk(
2018 ext4_rec_len_from_disk(pde->rec_len,
2019 blocksize) +
2020 ext4_rec_len_from_disk(de->rec_len,
2021 blocksize),
2022 blocksize);
2023 else
2024 de->inode = 0;
2025 dir->i_version++;
2026 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2027 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
2028 if (unlikely(err)) {
2029 ext4_std_error(dir->i_sb, err);
2030 return err;
2031 }
2032 return 0;
2033 }
2034 i += ext4_rec_len_from_disk(de->rec_len, blocksize);
2035 pde = de;
2036 de = ext4_next_entry(de, blocksize);
2037 }
2038 return -ENOENT;
2039}
2040
2041/*
2042 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2,
2043 * since this indicates that nlinks count was previously 1.
2044 */
2045static void ext4_inc_count(handle_t *handle, struct inode *inode)
2046{
2047 inc_nlink(inode);
2048 if (is_dx(inode) && inode->i_nlink > 1) {
2049 /* limit is 16-bit i_links_count */
2050 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) {
2051 set_nlink(inode, 1);
2052 EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb,
2053 EXT4_FEATURE_RO_COMPAT_DIR_NLINK);
2054 }
2055 }
2056}
2057
2058/*
2059 * If a directory had nlink == 1, then we should let it be 1. This indicates
2060 * directory has >EXT4_LINK_MAX subdirs.
2061 */
2062static void ext4_dec_count(handle_t *handle, struct inode *inode)
2063{
2064 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2065 drop_nlink(inode);
2066}
2067
2068
2069static int ext4_add_nondir(handle_t *handle,
2070 struct dentry *dentry, struct inode *inode)
2071{
2072 int err = ext4_add_entry(handle, dentry, inode);
2073 if (!err) {
2074 ext4_mark_inode_dirty(handle, inode);
2075 d_instantiate(dentry, inode);
2076 unlock_new_inode(inode);
2077 return 0;
2078 }
2079 drop_nlink(inode);
2080 unlock_new_inode(inode);
2081 iput(inode);
2082 return err;
2083}
2084
2085/*
2086 * By the time this is called, we already have created
2087 * the directory cache entry for the new file, but it
2088 * is so far negative - it has no inode.
2089 *
2090 * If the create succeeds, we fill in the inode information
2091 * with d_instantiate().
2092 */
2093static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
2094 struct nameidata *nd)
2095{
2096 handle_t *handle;
2097 struct inode *inode;
2098 int err, retries = 0;
2099
2100 dquot_initialize(dir);
2101
2102retry:
2103 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2104 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2105 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
2106 if (IS_ERR(handle))
2107 return PTR_ERR(handle);
2108
2109 if (IS_DIRSYNC(dir))
2110 ext4_handle_sync(handle);
2111
2112 inode = ext4_new_inode(handle, dir, mode, &dentry->d_name, 0, NULL);
2113 err = PTR_ERR(inode);
2114 if (!IS_ERR(inode)) {
2115 inode->i_op = &ext4_file_inode_operations;
2116 inode->i_fop = &ext4_file_operations;
2117 ext4_set_aops(inode);
2118 err = ext4_add_nondir(handle, dentry, inode);
2119 }
2120 ext4_journal_stop(handle);
2121 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2122 goto retry;
2123 return err;
2124}
2125
2126static int ext4_mknod(struct inode *dir, struct dentry *dentry,
2127 umode_t mode, dev_t rdev)
2128{
2129 handle_t *handle;
2130 struct inode *inode;
2131 int err, retries = 0;
2132
2133 if (!new_valid_dev(rdev))
2134 return -EINVAL;
2135
2136 dquot_initialize(dir);
2137
2138retry:
2139 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2140 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2141 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
2142 if (IS_ERR(handle))
2143 return PTR_ERR(handle);
2144
2145 if (IS_DIRSYNC(dir))
2146 ext4_handle_sync(handle);
2147
2148 inode = ext4_new_inode(handle, dir, mode, &dentry->d_name, 0, NULL);
2149 err = PTR_ERR(inode);
2150 if (!IS_ERR(inode)) {
2151 init_special_inode(inode, inode->i_mode, rdev);
2152#ifdef CONFIG_EXT4_FS_XATTR
2153 inode->i_op = &ext4_special_inode_operations;
2154#endif
2155 err = ext4_add_nondir(handle, dentry, inode);
2156 }
2157 ext4_journal_stop(handle);
2158 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2159 goto retry;
2160 return err;
2161}
2162
2163static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2164{
2165 handle_t *handle;
2166 struct inode *inode;
2167 struct buffer_head *dir_block = NULL;
2168 struct ext4_dir_entry_2 *de;
2169 struct ext4_dir_entry_tail *t;
2170 unsigned int blocksize = dir->i_sb->s_blocksize;
2171 int csum_size = 0;
2172 int err, retries = 0;
2173
2174 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2175 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2176 csum_size = sizeof(struct ext4_dir_entry_tail);
2177
2178 if (EXT4_DIR_LINK_MAX(dir))
2179 return -EMLINK;
2180
2181 dquot_initialize(dir);
2182
2183retry:
2184 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2185 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2186 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
2187 if (IS_ERR(handle))
2188 return PTR_ERR(handle);
2189
2190 if (IS_DIRSYNC(dir))
2191 ext4_handle_sync(handle);
2192
2193 inode = ext4_new_inode(handle, dir, S_IFDIR | mode,
2194 &dentry->d_name, 0, NULL);
2195 err = PTR_ERR(inode);
2196 if (IS_ERR(inode))
2197 goto out_stop;
2198
2199 inode->i_op = &ext4_dir_inode_operations;
2200 inode->i_fop = &ext4_dir_operations;
2201 inode->i_size = EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
2202 dir_block = ext4_bread(handle, inode, 0, 1, &err);
2203 if (!dir_block)
2204 goto out_clear_inode;
2205 BUFFER_TRACE(dir_block, "get_write_access");
2206 err = ext4_journal_get_write_access(handle, dir_block);
2207 if (err)
2208 goto out_clear_inode;
2209 de = (struct ext4_dir_entry_2 *) dir_block->b_data;
2210 de->inode = cpu_to_le32(inode->i_ino);
2211 de->name_len = 1;
2212 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2213 blocksize);
2214 strcpy(de->name, ".");
2215 ext4_set_de_type(dir->i_sb, de, S_IFDIR);
2216 de = ext4_next_entry(de, blocksize);
2217 de->inode = cpu_to_le32(dir->i_ino);
2218 de->rec_len = ext4_rec_len_to_disk(blocksize -
2219 (csum_size + EXT4_DIR_REC_LEN(1)),
2220 blocksize);
2221 de->name_len = 2;
2222 strcpy(de->name, "..");
2223 ext4_set_de_type(dir->i_sb, de, S_IFDIR);
2224 set_nlink(inode, 2);
2225
2226 if (csum_size) {
2227 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
2228 initialize_dirent_tail(t, blocksize);
2229 }
2230
2231 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2232 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
2233 if (err)
2234 goto out_clear_inode;
2235 set_buffer_verified(dir_block);
2236 err = ext4_mark_inode_dirty(handle, inode);
2237 if (!err)
2238 err = ext4_add_entry(handle, dentry, inode);
2239 if (err) {
2240out_clear_inode:
2241 clear_nlink(inode);
2242 unlock_new_inode(inode);
2243 ext4_mark_inode_dirty(handle, inode);
2244 iput(inode);
2245 goto out_stop;
2246 }
2247 ext4_inc_count(handle, dir);
2248 ext4_update_dx_flag(dir);
2249 err = ext4_mark_inode_dirty(handle, dir);
2250 if (err)
2251 goto out_clear_inode;
2252 d_instantiate(dentry, inode);
2253 unlock_new_inode(inode);
2254out_stop:
2255 brelse(dir_block);
2256 ext4_journal_stop(handle);
2257 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2258 goto retry;
2259 return err;
2260}
2261
2262/*
2263 * routine to check that the specified directory is empty (for rmdir)
2264 */
2265static int empty_dir(struct inode *inode)
2266{
2267 unsigned int offset;
2268 struct buffer_head *bh;
2269 struct ext4_dir_entry_2 *de, *de1;
2270 struct super_block *sb;
2271 int err = 0;
2272
2273 sb = inode->i_sb;
2274 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2) ||
2275 !(bh = ext4_bread(NULL, inode, 0, 0, &err))) {
2276 if (err)
2277 EXT4_ERROR_INODE(inode,
2278 "error %d reading directory lblock 0", err);
2279 else
2280 ext4_warning(inode->i_sb,
2281 "bad directory (dir #%lu) - no data block",
2282 inode->i_ino);
2283 return 1;
2284 }
2285 if (!buffer_verified(bh) &&
2286 !ext4_dirent_csum_verify(inode,
2287 (struct ext4_dir_entry *)bh->b_data)) {
2288 EXT4_ERROR_INODE(inode, "checksum error reading directory "
2289 "lblock 0");
2290 return -EIO;
2291 }
2292 set_buffer_verified(bh);
2293 de = (struct ext4_dir_entry_2 *) bh->b_data;
2294 de1 = ext4_next_entry(de, sb->s_blocksize);
2295 if (le32_to_cpu(de->inode) != inode->i_ino ||
2296 !le32_to_cpu(de1->inode) ||
2297 strcmp(".", de->name) ||
2298 strcmp("..", de1->name)) {
2299 ext4_warning(inode->i_sb,
2300 "bad directory (dir #%lu) - no `.' or `..'",
2301 inode->i_ino);
2302 brelse(bh);
2303 return 1;
2304 }
2305 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
2306 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
2307 de = ext4_next_entry(de1, sb->s_blocksize);
2308 while (offset < inode->i_size) {
2309 if (!bh ||
2310 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
2311 unsigned int lblock;
2312 err = 0;
2313 brelse(bh);
2314 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
2315 bh = ext4_bread(NULL, inode, lblock, 0, &err);
2316 if (!bh) {
2317 if (err)
2318 EXT4_ERROR_INODE(inode,
2319 "error %d reading directory "
2320 "lblock %u", err, lblock);
2321 offset += sb->s_blocksize;
2322 continue;
2323 }
2324 if (!buffer_verified(bh) &&
2325 !ext4_dirent_csum_verify(inode,
2326 (struct ext4_dir_entry *)bh->b_data)) {
2327 EXT4_ERROR_INODE(inode, "checksum error "
2328 "reading directory lblock 0");
2329 return -EIO;
2330 }
2331 set_buffer_verified(bh);
2332 de = (struct ext4_dir_entry_2 *) bh->b_data;
2333 }
2334 if (ext4_check_dir_entry(inode, NULL, de, bh, offset)) {
2335 de = (struct ext4_dir_entry_2 *)(bh->b_data +
2336 sb->s_blocksize);
2337 offset = (offset | (sb->s_blocksize - 1)) + 1;
2338 continue;
2339 }
2340 if (le32_to_cpu(de->inode)) {
2341 brelse(bh);
2342 return 0;
2343 }
2344 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2345 de = ext4_next_entry(de, sb->s_blocksize);
2346 }
2347 brelse(bh);
2348 return 1;
2349}
2350
2351/* ext4_orphan_add() links an unlinked or truncated inode into a list of
2352 * such inodes, starting at the superblock, in case we crash before the
2353 * file is closed/deleted, or in case the inode truncate spans multiple
2354 * transactions and the last transaction is not recovered after a crash.
2355 *
2356 * At filesystem recovery time, we walk this list deleting unlinked
2357 * inodes and truncating linked inodes in ext4_orphan_cleanup().
2358 */
2359int ext4_orphan_add(handle_t *handle, struct inode *inode)
2360{
2361 struct super_block *sb = inode->i_sb;
2362 struct ext4_iloc iloc;
2363 int err = 0, rc;
2364
2365 if (!ext4_handle_valid(handle))
2366 return 0;
2367
2368 mutex_lock(&EXT4_SB(sb)->s_orphan_lock);
2369 if (!list_empty(&EXT4_I(inode)->i_orphan))
2370 goto out_unlock;
2371
2372 /*
2373 * Orphan handling is only valid for files with data blocks
2374 * being truncated, or files being unlinked. Note that we either
2375 * hold i_mutex, or the inode can not be referenced from outside,
2376 * so i_nlink should not be bumped due to race
2377 */
2378 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2379 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
2380
2381 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
2382 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
2383 if (err)
2384 goto out_unlock;
2385
2386 err = ext4_reserve_inode_write(handle, inode, &iloc);
2387 if (err)
2388 goto out_unlock;
2389 /*
2390 * Due to previous errors inode may be already a part of on-disk
2391 * orphan list. If so skip on-disk list modification.
2392 */
2393 if (NEXT_ORPHAN(inode) && NEXT_ORPHAN(inode) <=
2394 (le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)))
2395 goto mem_insert;
2396
2397 /* Insert this inode at the head of the on-disk orphan list... */
2398 NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan);
2399 EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2400 err = ext4_handle_dirty_super_now(handle, sb);
2401 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
2402 if (!err)
2403 err = rc;
2404
2405 /* Only add to the head of the in-memory list if all the
2406 * previous operations succeeded. If the orphan_add is going to
2407 * fail (possibly taking the journal offline), we can't risk
2408 * leaving the inode on the orphan list: stray orphan-list
2409 * entries can cause panics at unmount time.
2410 *
2411 * This is safe: on error we're going to ignore the orphan list
2412 * anyway on the next recovery. */
2413mem_insert:
2414 if (!err)
2415 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2416
2417 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
2418 jbd_debug(4, "orphan inode %lu will point to %d\n",
2419 inode->i_ino, NEXT_ORPHAN(inode));
2420out_unlock:
2421 mutex_unlock(&EXT4_SB(sb)->s_orphan_lock);
2422 ext4_std_error(inode->i_sb, err);
2423 return err;
2424}
2425
2426/*
2427 * ext4_orphan_del() removes an unlinked or truncated inode from the list
2428 * of such inodes stored on disk, because it is finally being cleaned up.
2429 */
2430int ext4_orphan_del(handle_t *handle, struct inode *inode)
2431{
2432 struct list_head *prev;
2433 struct ext4_inode_info *ei = EXT4_I(inode);
2434 struct ext4_sb_info *sbi;
2435 __u32 ino_next;
2436 struct ext4_iloc iloc;
2437 int err = 0;
2438
2439 /* ext4_handle_valid() assumes a valid handle_t pointer */
2440 if (handle && !ext4_handle_valid(handle))
2441 return 0;
2442
2443 mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
2444 if (list_empty(&ei->i_orphan))
2445 goto out;
2446
2447 ino_next = NEXT_ORPHAN(inode);
2448 prev = ei->i_orphan.prev;
2449 sbi = EXT4_SB(inode->i_sb);
2450
2451 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
2452
2453 list_del_init(&ei->i_orphan);
2454
2455 /* If we're on an error path, we may not have a valid
2456 * transaction handle with which to update the orphan list on
2457 * disk, but we still need to remove the inode from the linked
2458 * list in memory. */
2459 if (sbi->s_journal && !handle)
2460 goto out;
2461
2462 err = ext4_reserve_inode_write(handle, inode, &iloc);
2463 if (err)
2464 goto out_err;
2465
2466 if (prev == &sbi->s_orphan) {
2467 jbd_debug(4, "superblock will point to %u\n", ino_next);
2468 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2469 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
2470 if (err)
2471 goto out_brelse;
2472 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
2473 err = ext4_handle_dirty_super_now(handle, inode->i_sb);
2474 } else {
2475 struct ext4_iloc iloc2;
2476 struct inode *i_prev =
2477 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
2478
2479 jbd_debug(4, "orphan inode %lu will point to %u\n",
2480 i_prev->i_ino, ino_next);
2481 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
2482 if (err)
2483 goto out_brelse;
2484 NEXT_ORPHAN(i_prev) = ino_next;
2485 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
2486 }
2487 if (err)
2488 goto out_brelse;
2489 NEXT_ORPHAN(inode) = 0;
2490 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
2491
2492out_err:
2493 ext4_std_error(inode->i_sb, err);
2494out:
2495 mutex_unlock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
2496 return err;
2497
2498out_brelse:
2499 brelse(iloc.bh);
2500 goto out_err;
2501}
2502
2503static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
2504{
2505 int retval;
2506 struct inode *inode;
2507 struct buffer_head *bh;
2508 struct ext4_dir_entry_2 *de;
2509 handle_t *handle;
2510
2511 /* Initialize quotas before so that eventual writes go in
2512 * separate transaction */
2513 dquot_initialize(dir);
2514 dquot_initialize(dentry->d_inode);
2515
2516 handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
2517 if (IS_ERR(handle))
2518 return PTR_ERR(handle);
2519
2520 retval = -ENOENT;
2521 bh = ext4_find_entry(dir, &dentry->d_name, &de);
2522 if (!bh)
2523 goto end_rmdir;
2524
2525 if (IS_DIRSYNC(dir))
2526 ext4_handle_sync(handle);
2527
2528 inode = dentry->d_inode;
2529
2530 retval = -EIO;
2531 if (le32_to_cpu(de->inode) != inode->i_ino)
2532 goto end_rmdir;
2533
2534 retval = -ENOTEMPTY;
2535 if (!empty_dir(inode))
2536 goto end_rmdir;
2537
2538 retval = ext4_delete_entry(handle, dir, de, bh);
2539 if (retval)
2540 goto end_rmdir;
2541 if (!EXT4_DIR_LINK_EMPTY(inode))
2542 ext4_warning(inode->i_sb,
2543 "empty directory has too many links (%d)",
2544 inode->i_nlink);
2545 inode->i_version++;
2546 clear_nlink(inode);
2547 /* There's no need to set i_disksize: the fact that i_nlink is
2548 * zero will ensure that the right thing happens during any
2549 * recovery. */
2550 inode->i_size = 0;
2551 ext4_orphan_add(handle, inode);
2552 inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode);
2553 ext4_mark_inode_dirty(handle, inode);
2554 ext4_dec_count(handle, dir);
2555 ext4_update_dx_flag(dir);
2556 ext4_mark_inode_dirty(handle, dir);
2557
2558end_rmdir:
2559 ext4_journal_stop(handle);
2560 brelse(bh);
2561 return retval;
2562}
2563
2564static int ext4_unlink(struct inode *dir, struct dentry *dentry)
2565{
2566 int retval;
2567 struct inode *inode;
2568 struct buffer_head *bh;
2569 struct ext4_dir_entry_2 *de;
2570 handle_t *handle;
2571
2572 trace_ext4_unlink_enter(dir, dentry);
2573 /* Initialize quotas before so that eventual writes go
2574 * in separate transaction */
2575 dquot_initialize(dir);
2576 dquot_initialize(dentry->d_inode);
2577
2578 handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
2579 if (IS_ERR(handle))
2580 return PTR_ERR(handle);
2581
2582 if (IS_DIRSYNC(dir))
2583 ext4_handle_sync(handle);
2584
2585 retval = -ENOENT;
2586 bh = ext4_find_entry(dir, &dentry->d_name, &de);
2587 if (!bh)
2588 goto end_unlink;
2589
2590 inode = dentry->d_inode;
2591
2592 retval = -EIO;
2593 if (le32_to_cpu(de->inode) != inode->i_ino)
2594 goto end_unlink;
2595
2596 if (!inode->i_nlink) {
2597 ext4_warning(inode->i_sb,
2598 "Deleting nonexistent file (%lu), %d",
2599 inode->i_ino, inode->i_nlink);
2600 set_nlink(inode, 1);
2601 }
2602 retval = ext4_delete_entry(handle, dir, de, bh);
2603 if (retval)
2604 goto end_unlink;
2605 dir->i_ctime = dir->i_mtime = ext4_current_time(dir);
2606 ext4_update_dx_flag(dir);
2607 ext4_mark_inode_dirty(handle, dir);
2608 drop_nlink(inode);
2609 if (!inode->i_nlink)
2610 ext4_orphan_add(handle, inode);
2611 inode->i_ctime = ext4_current_time(inode);
2612 ext4_mark_inode_dirty(handle, inode);
2613 retval = 0;
2614
2615end_unlink:
2616 ext4_journal_stop(handle);
2617 brelse(bh);
2618 trace_ext4_unlink_exit(dentry, retval);
2619 return retval;
2620}
2621
2622static int ext4_symlink(struct inode *dir,
2623 struct dentry *dentry, const char *symname)
2624{
2625 handle_t *handle;
2626 struct inode *inode;
2627 int l, err, retries = 0;
2628 int credits;
2629
2630 l = strlen(symname)+1;
2631 if (l > dir->i_sb->s_blocksize)
2632 return -ENAMETOOLONG;
2633
2634 dquot_initialize(dir);
2635
2636 if (l > EXT4_N_BLOCKS * 4) {
2637 /*
2638 * For non-fast symlinks, we just allocate inode and put it on
2639 * orphan list in the first transaction => we need bitmap,
2640 * group descriptor, sb, inode block, quota blocks, and
2641 * possibly selinux xattr blocks.
2642 */
2643 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2644 EXT4_XATTR_TRANS_BLOCKS;
2645 } else {
2646 /*
2647 * Fast symlink. We have to add entry to directory
2648 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
2649 * allocate new inode (bitmap, group descriptor, inode block,
2650 * quota blocks, sb is already counted in previous macros).
2651 */
2652 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2653 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2654 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb);
2655 }
2656retry:
2657 handle = ext4_journal_start(dir, credits);
2658 if (IS_ERR(handle))
2659 return PTR_ERR(handle);
2660
2661 if (IS_DIRSYNC(dir))
2662 ext4_handle_sync(handle);
2663
2664 inode = ext4_new_inode(handle, dir, S_IFLNK|S_IRWXUGO,
2665 &dentry->d_name, 0, NULL);
2666 err = PTR_ERR(inode);
2667 if (IS_ERR(inode))
2668 goto out_stop;
2669
2670 if (l > EXT4_N_BLOCKS * 4) {
2671 inode->i_op = &ext4_symlink_inode_operations;
2672 ext4_set_aops(inode);
2673 /*
2674 * We cannot call page_symlink() with transaction started
2675 * because it calls into ext4_write_begin() which can wait
2676 * for transaction commit if we are running out of space
2677 * and thus we deadlock. So we have to stop transaction now
2678 * and restart it when symlink contents is written.
2679 *
2680 * To keep fs consistent in case of crash, we have to put inode
2681 * to orphan list in the mean time.
2682 */
2683 drop_nlink(inode);
2684 err = ext4_orphan_add(handle, inode);
2685 ext4_journal_stop(handle);
2686 if (err)
2687 goto err_drop_inode;
2688 err = __page_symlink(inode, symname, l, 1);
2689 if (err)
2690 goto err_drop_inode;
2691 /*
2692 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
2693 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
2694 */
2695 handle = ext4_journal_start(dir,
2696 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2697 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
2698 if (IS_ERR(handle)) {
2699 err = PTR_ERR(handle);
2700 goto err_drop_inode;
2701 }
2702 set_nlink(inode, 1);
2703 err = ext4_orphan_del(handle, inode);
2704 if (err) {
2705 ext4_journal_stop(handle);
2706 clear_nlink(inode);
2707 goto err_drop_inode;
2708 }
2709 } else {
2710 /* clear the extent format for fast symlink */
2711 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
2712 inode->i_op = &ext4_fast_symlink_inode_operations;
2713 memcpy((char *)&EXT4_I(inode)->i_data, symname, l);
2714 inode->i_size = l-1;
2715 }
2716 EXT4_I(inode)->i_disksize = inode->i_size;
2717 err = ext4_add_nondir(handle, dentry, inode);
2718out_stop:
2719 ext4_journal_stop(handle);
2720 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2721 goto retry;
2722 return err;
2723err_drop_inode:
2724 unlock_new_inode(inode);
2725 iput(inode);
2726 return err;
2727}
2728
2729static int ext4_link(struct dentry *old_dentry,
2730 struct inode *dir, struct dentry *dentry)
2731{
2732 handle_t *handle;
2733 struct inode *inode = old_dentry->d_inode;
2734 int err, retries = 0;
2735
2736 if (inode->i_nlink >= EXT4_LINK_MAX)
2737 return -EMLINK;
2738
2739 dquot_initialize(dir);
2740
2741retry:
2742 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2743 EXT4_INDEX_EXTRA_TRANS_BLOCKS);
2744 if (IS_ERR(handle))
2745 return PTR_ERR(handle);
2746
2747 if (IS_DIRSYNC(dir))
2748 ext4_handle_sync(handle);
2749
2750 inode->i_ctime = ext4_current_time(inode);
2751 ext4_inc_count(handle, inode);
2752 ihold(inode);
2753
2754 err = ext4_add_entry(handle, dentry, inode);
2755 if (!err) {
2756 ext4_mark_inode_dirty(handle, inode);
2757 d_instantiate(dentry, inode);
2758 } else {
2759 drop_nlink(inode);
2760 iput(inode);
2761 }
2762 ext4_journal_stop(handle);
2763 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2764 goto retry;
2765 return err;
2766}
2767
2768#define PARENT_INO(buffer, size) \
2769 (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer), size)->inode)
2770
2771/*
2772 * Anybody can rename anything with this: the permission checks are left to the
2773 * higher-level routines.
2774 */
2775static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
2776 struct inode *new_dir, struct dentry *new_dentry)
2777{
2778 handle_t *handle;
2779 struct inode *old_inode, *new_inode;
2780 struct buffer_head *old_bh, *new_bh, *dir_bh;
2781 struct ext4_dir_entry_2 *old_de, *new_de;
2782 int retval, force_da_alloc = 0;
2783
2784 dquot_initialize(old_dir);
2785 dquot_initialize(new_dir);
2786
2787 old_bh = new_bh = dir_bh = NULL;
2788
2789 /* Initialize quotas before so that eventual writes go
2790 * in separate transaction */
2791 if (new_dentry->d_inode)
2792 dquot_initialize(new_dentry->d_inode);
2793 handle = ext4_journal_start(old_dir, 2 *
2794 EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) +
2795 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
2796 if (IS_ERR(handle))
2797 return PTR_ERR(handle);
2798
2799 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
2800 ext4_handle_sync(handle);
2801
2802 old_bh = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de);
2803 /*
2804 * Check for inode number is _not_ due to possible IO errors.
2805 * We might rmdir the source, keep it as pwd of some process
2806 * and merrily kill the link to whatever was created under the
2807 * same name. Goodbye sticky bit ;-<
2808 */
2809 old_inode = old_dentry->d_inode;
2810 retval = -ENOENT;
2811 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
2812 goto end_rename;
2813
2814 new_inode = new_dentry->d_inode;
2815 new_bh = ext4_find_entry(new_dir, &new_dentry->d_name, &new_de);
2816 if (new_bh) {
2817 if (!new_inode) {
2818 brelse(new_bh);
2819 new_bh = NULL;
2820 }
2821 }
2822 if (S_ISDIR(old_inode->i_mode)) {
2823 if (new_inode) {
2824 retval = -ENOTEMPTY;
2825 if (!empty_dir(new_inode))
2826 goto end_rename;
2827 }
2828 retval = -EIO;
2829 dir_bh = ext4_bread(handle, old_inode, 0, 0, &retval);
2830 if (!dir_bh)
2831 goto end_rename;
2832 if (!buffer_verified(dir_bh) &&
2833 !ext4_dirent_csum_verify(old_inode,
2834 (struct ext4_dir_entry *)dir_bh->b_data))
2835 goto end_rename;
2836 set_buffer_verified(dir_bh);
2837 if (le32_to_cpu(PARENT_INO(dir_bh->b_data,
2838 old_dir->i_sb->s_blocksize)) != old_dir->i_ino)
2839 goto end_rename;
2840 retval = -EMLINK;
2841 if (!new_inode && new_dir != old_dir &&
2842 EXT4_DIR_LINK_MAX(new_dir))
2843 goto end_rename;
2844 BUFFER_TRACE(dir_bh, "get_write_access");
2845 retval = ext4_journal_get_write_access(handle, dir_bh);
2846 if (retval)
2847 goto end_rename;
2848 }
2849 if (!new_bh) {
2850 retval = ext4_add_entry(handle, new_dentry, old_inode);
2851 if (retval)
2852 goto end_rename;
2853 } else {
2854 BUFFER_TRACE(new_bh, "get write access");
2855 retval = ext4_journal_get_write_access(handle, new_bh);
2856 if (retval)
2857 goto end_rename;
2858 new_de->inode = cpu_to_le32(old_inode->i_ino);
2859 if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
2860 EXT4_FEATURE_INCOMPAT_FILETYPE))
2861 new_de->file_type = old_de->file_type;
2862 new_dir->i_version++;
2863 new_dir->i_ctime = new_dir->i_mtime =
2864 ext4_current_time(new_dir);
2865 ext4_mark_inode_dirty(handle, new_dir);
2866 BUFFER_TRACE(new_bh, "call ext4_handle_dirty_metadata");
2867 retval = ext4_handle_dirty_dirent_node(handle, new_dir, new_bh);
2868 if (unlikely(retval)) {
2869 ext4_std_error(new_dir->i_sb, retval);
2870 goto end_rename;
2871 }
2872 brelse(new_bh);
2873 new_bh = NULL;
2874 }
2875
2876 /*
2877 * Like most other Unix systems, set the ctime for inodes on a
2878 * rename.
2879 */
2880 old_inode->i_ctime = ext4_current_time(old_inode);
2881 ext4_mark_inode_dirty(handle, old_inode);
2882
2883 /*
2884 * ok, that's it
2885 */
2886 if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
2887 old_de->name_len != old_dentry->d_name.len ||
2888 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
2889 (retval = ext4_delete_entry(handle, old_dir,
2890 old_de, old_bh)) == -ENOENT) {
2891 /* old_de could have moved from under us during htree split, so
2892 * make sure that we are deleting the right entry. We might
2893 * also be pointing to a stale entry in the unused part of
2894 * old_bh so just checking inum and the name isn't enough. */
2895 struct buffer_head *old_bh2;
2896 struct ext4_dir_entry_2 *old_de2;
2897
2898 old_bh2 = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de2);
2899 if (old_bh2) {
2900 retval = ext4_delete_entry(handle, old_dir,
2901 old_de2, old_bh2);
2902 brelse(old_bh2);
2903 }
2904 }
2905 if (retval) {
2906 ext4_warning(old_dir->i_sb,
2907 "Deleting old file (%lu), %d, error=%d",
2908 old_dir->i_ino, old_dir->i_nlink, retval);
2909 }
2910
2911 if (new_inode) {
2912 ext4_dec_count(handle, new_inode);
2913 new_inode->i_ctime = ext4_current_time(new_inode);
2914 }
2915 old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir);
2916 ext4_update_dx_flag(old_dir);
2917 if (dir_bh) {
2918 PARENT_INO(dir_bh->b_data, new_dir->i_sb->s_blocksize) =
2919 cpu_to_le32(new_dir->i_ino);
2920 BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata");
2921 if (is_dx(old_inode)) {
2922 retval = ext4_handle_dirty_dx_node(handle,
2923 old_inode,
2924 dir_bh);
2925 } else {
2926 retval = ext4_handle_dirty_dirent_node(handle,
2927 old_inode,
2928 dir_bh);
2929 }
2930 if (retval) {
2931 ext4_std_error(old_dir->i_sb, retval);
2932 goto end_rename;
2933 }
2934 ext4_dec_count(handle, old_dir);
2935 if (new_inode) {
2936 /* checked empty_dir above, can't have another parent,
2937 * ext4_dec_count() won't work for many-linked dirs */
2938 clear_nlink(new_inode);
2939 } else {
2940 ext4_inc_count(handle, new_dir);
2941 ext4_update_dx_flag(new_dir);
2942 ext4_mark_inode_dirty(handle, new_dir);
2943 }
2944 }
2945 ext4_mark_inode_dirty(handle, old_dir);
2946 if (new_inode) {
2947 ext4_mark_inode_dirty(handle, new_inode);
2948 if (!new_inode->i_nlink)
2949 ext4_orphan_add(handle, new_inode);
2950 if (!test_opt(new_dir->i_sb, NO_AUTO_DA_ALLOC))
2951 force_da_alloc = 1;
2952 }
2953 retval = 0;
2954
2955end_rename:
2956 brelse(dir_bh);
2957 brelse(old_bh);
2958 brelse(new_bh);
2959 ext4_journal_stop(handle);
2960 if (retval == 0 && force_da_alloc)
2961 ext4_alloc_da_blocks(old_inode);
2962 return retval;
2963}
2964
2965/*
2966 * directories can handle most operations...
2967 */
2968const struct inode_operations ext4_dir_inode_operations = {
2969 .create = ext4_create,
2970 .lookup = ext4_lookup,
2971 .link = ext4_link,
2972 .unlink = ext4_unlink,
2973 .symlink = ext4_symlink,
2974 .mkdir = ext4_mkdir,
2975 .rmdir = ext4_rmdir,
2976 .mknod = ext4_mknod,
2977 .rename = ext4_rename,
2978 .setattr = ext4_setattr,
2979#ifdef CONFIG_EXT4_FS_XATTR
2980 .setxattr = generic_setxattr,
2981 .getxattr = generic_getxattr,
2982 .listxattr = ext4_listxattr,
2983 .removexattr = generic_removexattr,
2984#endif
2985 .get_acl = ext4_get_acl,
2986 .fiemap = ext4_fiemap,
2987};
2988
2989const struct inode_operations ext4_special_inode_operations = {
2990 .setattr = ext4_setattr,
2991#ifdef CONFIG_EXT4_FS_XATTR
2992 .setxattr = generic_setxattr,
2993 .getxattr = generic_getxattr,
2994 .listxattr = ext4_listxattr,
2995 .removexattr = generic_removexattr,
2996#endif
2997 .get_acl = ext4_get_acl,
2998};
1/*
2 * linux/fs/ext4/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/fs.h>
28#include <linux/pagemap.h>
29#include <linux/jbd2.h>
30#include <linux/time.h>
31#include <linux/fcntl.h>
32#include <linux/stat.h>
33#include <linux/string.h>
34#include <linux/quotaops.h>
35#include <linux/buffer_head.h>
36#include <linux/bio.h>
37#include "ext4.h"
38#include "ext4_jbd2.h"
39
40#include "xattr.h"
41#include "acl.h"
42
43#include <trace/events/ext4.h>
44/*
45 * define how far ahead to read directories while searching them.
46 */
47#define NAMEI_RA_CHUNKS 2
48#define NAMEI_RA_BLOCKS 4
49#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
50
51static struct buffer_head *ext4_append(handle_t *handle,
52 struct inode *inode,
53 ext4_lblk_t *block)
54{
55 struct buffer_head *bh;
56 int err = 0;
57
58 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
59 ((inode->i_size >> 10) >=
60 EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
61 return ERR_PTR(-ENOSPC);
62
63 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
64
65 bh = ext4_bread(handle, inode, *block, 1, &err);
66 if (!bh)
67 return ERR_PTR(err);
68 inode->i_size += inode->i_sb->s_blocksize;
69 EXT4_I(inode)->i_disksize = inode->i_size;
70 err = ext4_journal_get_write_access(handle, bh);
71 if (err) {
72 brelse(bh);
73 ext4_std_error(inode->i_sb, err);
74 return ERR_PTR(err);
75 }
76 return bh;
77}
78
79static int ext4_dx_csum_verify(struct inode *inode,
80 struct ext4_dir_entry *dirent);
81
82typedef enum {
83 EITHER, INDEX, DIRENT
84} dirblock_type_t;
85
86#define ext4_read_dirblock(inode, block, type) \
87 __ext4_read_dirblock((inode), (block), (type), __LINE__)
88
89static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
90 ext4_lblk_t block,
91 dirblock_type_t type,
92 unsigned int line)
93{
94 struct buffer_head *bh;
95 struct ext4_dir_entry *dirent;
96 int err = 0, is_dx_block = 0;
97
98 bh = ext4_bread(NULL, inode, block, 0, &err);
99 if (!bh) {
100 if (err == 0) {
101 ext4_error_inode(inode, __func__, line, block,
102 "Directory hole found");
103 return ERR_PTR(-EIO);
104 }
105 __ext4_warning(inode->i_sb, __func__, line,
106 "error reading directory block "
107 "(ino %lu, block %lu)", inode->i_ino,
108 (unsigned long) block);
109 return ERR_PTR(err);
110 }
111 dirent = (struct ext4_dir_entry *) bh->b_data;
112 /* Determine whether or not we have an index block */
113 if (is_dx(inode)) {
114 if (block == 0)
115 is_dx_block = 1;
116 else if (ext4_rec_len_from_disk(dirent->rec_len,
117 inode->i_sb->s_blocksize) ==
118 inode->i_sb->s_blocksize)
119 is_dx_block = 1;
120 }
121 if (!is_dx_block && type == INDEX) {
122 ext4_error_inode(inode, __func__, line, block,
123 "directory leaf block found instead of index block");
124 return ERR_PTR(-EIO);
125 }
126 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
127 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) ||
128 buffer_verified(bh))
129 return bh;
130
131 /*
132 * An empty leaf block can get mistaken for a index block; for
133 * this reason, we can only check the index checksum when the
134 * caller is sure it should be an index block.
135 */
136 if (is_dx_block && type == INDEX) {
137 if (ext4_dx_csum_verify(inode, dirent))
138 set_buffer_verified(bh);
139 else {
140 ext4_error_inode(inode, __func__, line, block,
141 "Directory index failed checksum");
142 brelse(bh);
143 return ERR_PTR(-EIO);
144 }
145 }
146 if (!is_dx_block) {
147 if (ext4_dirent_csum_verify(inode, dirent))
148 set_buffer_verified(bh);
149 else {
150 ext4_error_inode(inode, __func__, line, block,
151 "Directory block failed checksum");
152 brelse(bh);
153 return ERR_PTR(-EIO);
154 }
155 }
156 return bh;
157}
158
159#ifndef assert
160#define assert(test) J_ASSERT(test)
161#endif
162
163#ifdef DX_DEBUG
164#define dxtrace(command) command
165#else
166#define dxtrace(command)
167#endif
168
169struct fake_dirent
170{
171 __le32 inode;
172 __le16 rec_len;
173 u8 name_len;
174 u8 file_type;
175};
176
177struct dx_countlimit
178{
179 __le16 limit;
180 __le16 count;
181};
182
183struct dx_entry
184{
185 __le32 hash;
186 __le32 block;
187};
188
189/*
190 * dx_root_info is laid out so that if it should somehow get overlaid by a
191 * dirent the two low bits of the hash version will be zero. Therefore, the
192 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
193 */
194
195struct dx_root
196{
197 struct fake_dirent dot;
198 char dot_name[4];
199 struct fake_dirent dotdot;
200 char dotdot_name[4];
201 struct dx_root_info
202 {
203 __le32 reserved_zero;
204 u8 hash_version;
205 u8 info_length; /* 8 */
206 u8 indirect_levels;
207 u8 unused_flags;
208 }
209 info;
210 struct dx_entry entries[0];
211};
212
213struct dx_node
214{
215 struct fake_dirent fake;
216 struct dx_entry entries[0];
217};
218
219
220struct dx_frame
221{
222 struct buffer_head *bh;
223 struct dx_entry *entries;
224 struct dx_entry *at;
225};
226
227struct dx_map_entry
228{
229 u32 hash;
230 u16 offs;
231 u16 size;
232};
233
234/*
235 * This goes at the end of each htree block.
236 */
237struct dx_tail {
238 u32 dt_reserved;
239 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
240};
241
242static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
243static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
244static inline unsigned dx_get_hash(struct dx_entry *entry);
245static void dx_set_hash(struct dx_entry *entry, unsigned value);
246static unsigned dx_get_count(struct dx_entry *entries);
247static unsigned dx_get_limit(struct dx_entry *entries);
248static void dx_set_count(struct dx_entry *entries, unsigned value);
249static void dx_set_limit(struct dx_entry *entries, unsigned value);
250static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
251static unsigned dx_node_limit(struct inode *dir);
252static struct dx_frame *dx_probe(const struct qstr *d_name,
253 struct inode *dir,
254 struct dx_hash_info *hinfo,
255 struct dx_frame *frame,
256 int *err);
257static void dx_release(struct dx_frame *frames);
258static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
259 struct dx_hash_info *hinfo, struct dx_map_entry map[]);
260static void dx_sort_map(struct dx_map_entry *map, unsigned count);
261static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
262 struct dx_map_entry *offsets, int count, unsigned blocksize);
263static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
264static void dx_insert_block(struct dx_frame *frame,
265 u32 hash, ext4_lblk_t block);
266static int ext4_htree_next_block(struct inode *dir, __u32 hash,
267 struct dx_frame *frame,
268 struct dx_frame *frames,
269 __u32 *start_hash);
270static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
271 const struct qstr *d_name,
272 struct ext4_dir_entry_2 **res_dir,
273 int *err);
274static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
275 struct inode *inode);
276
277/* checksumming functions */
278void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
279 unsigned int blocksize)
280{
281 memset(t, 0, sizeof(struct ext4_dir_entry_tail));
282 t->det_rec_len = ext4_rec_len_to_disk(
283 sizeof(struct ext4_dir_entry_tail), blocksize);
284 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
285}
286
287/* Walk through a dirent block to find a checksum "dirent" at the tail */
288static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
289 struct ext4_dir_entry *de)
290{
291 struct ext4_dir_entry_tail *t;
292
293#ifdef PARANOID
294 struct ext4_dir_entry *d, *top;
295
296 d = de;
297 top = (struct ext4_dir_entry *)(((void *)de) +
298 (EXT4_BLOCK_SIZE(inode->i_sb) -
299 sizeof(struct ext4_dir_entry_tail)));
300 while (d < top && d->rec_len)
301 d = (struct ext4_dir_entry *)(((void *)d) +
302 le16_to_cpu(d->rec_len));
303
304 if (d != top)
305 return NULL;
306
307 t = (struct ext4_dir_entry_tail *)d;
308#else
309 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
310#endif
311
312 if (t->det_reserved_zero1 ||
313 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
314 t->det_reserved_zero2 ||
315 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
316 return NULL;
317
318 return t;
319}
320
321static __le32 ext4_dirent_csum(struct inode *inode,
322 struct ext4_dir_entry *dirent, int size)
323{
324 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
325 struct ext4_inode_info *ei = EXT4_I(inode);
326 __u32 csum;
327
328 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
329 return cpu_to_le32(csum);
330}
331
332static void warn_no_space_for_csum(struct inode *inode)
333{
334 ext4_warning(inode->i_sb, "no space in directory inode %lu leaf for "
335 "checksum. Please run e2fsck -D.", inode->i_ino);
336}
337
338int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
339{
340 struct ext4_dir_entry_tail *t;
341
342 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
343 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
344 return 1;
345
346 t = get_dirent_tail(inode, dirent);
347 if (!t) {
348 warn_no_space_for_csum(inode);
349 return 0;
350 }
351
352 if (t->det_checksum != ext4_dirent_csum(inode, dirent,
353 (void *)t - (void *)dirent))
354 return 0;
355
356 return 1;
357}
358
359static void ext4_dirent_csum_set(struct inode *inode,
360 struct ext4_dir_entry *dirent)
361{
362 struct ext4_dir_entry_tail *t;
363
364 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
365 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
366 return;
367
368 t = get_dirent_tail(inode, dirent);
369 if (!t) {
370 warn_no_space_for_csum(inode);
371 return;
372 }
373
374 t->det_checksum = ext4_dirent_csum(inode, dirent,
375 (void *)t - (void *)dirent);
376}
377
378int ext4_handle_dirty_dirent_node(handle_t *handle,
379 struct inode *inode,
380 struct buffer_head *bh)
381{
382 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
383 return ext4_handle_dirty_metadata(handle, inode, bh);
384}
385
386static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
387 struct ext4_dir_entry *dirent,
388 int *offset)
389{
390 struct ext4_dir_entry *dp;
391 struct dx_root_info *root;
392 int count_offset;
393
394 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
395 count_offset = 8;
396 else if (le16_to_cpu(dirent->rec_len) == 12) {
397 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
398 if (le16_to_cpu(dp->rec_len) !=
399 EXT4_BLOCK_SIZE(inode->i_sb) - 12)
400 return NULL;
401 root = (struct dx_root_info *)(((void *)dp + 12));
402 if (root->reserved_zero ||
403 root->info_length != sizeof(struct dx_root_info))
404 return NULL;
405 count_offset = 32;
406 } else
407 return NULL;
408
409 if (offset)
410 *offset = count_offset;
411 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
412}
413
414static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
415 int count_offset, int count, struct dx_tail *t)
416{
417 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
418 struct ext4_inode_info *ei = EXT4_I(inode);
419 __u32 csum;
420 __le32 save_csum;
421 int size;
422
423 size = count_offset + (count * sizeof(struct dx_entry));
424 save_csum = t->dt_checksum;
425 t->dt_checksum = 0;
426 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
427 csum = ext4_chksum(sbi, csum, (__u8 *)t, sizeof(struct dx_tail));
428 t->dt_checksum = save_csum;
429
430 return cpu_to_le32(csum);
431}
432
433static int ext4_dx_csum_verify(struct inode *inode,
434 struct ext4_dir_entry *dirent)
435{
436 struct dx_countlimit *c;
437 struct dx_tail *t;
438 int count_offset, limit, count;
439
440 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
441 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
442 return 1;
443
444 c = get_dx_countlimit(inode, dirent, &count_offset);
445 if (!c) {
446 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
447 return 1;
448 }
449 limit = le16_to_cpu(c->limit);
450 count = le16_to_cpu(c->count);
451 if (count_offset + (limit * sizeof(struct dx_entry)) >
452 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
453 warn_no_space_for_csum(inode);
454 return 1;
455 }
456 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
457
458 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
459 count, t))
460 return 0;
461 return 1;
462}
463
464static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
465{
466 struct dx_countlimit *c;
467 struct dx_tail *t;
468 int count_offset, limit, count;
469
470 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
471 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
472 return;
473
474 c = get_dx_countlimit(inode, dirent, &count_offset);
475 if (!c) {
476 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
477 return;
478 }
479 limit = le16_to_cpu(c->limit);
480 count = le16_to_cpu(c->count);
481 if (count_offset + (limit * sizeof(struct dx_entry)) >
482 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
483 warn_no_space_for_csum(inode);
484 return;
485 }
486 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
487
488 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
489}
490
491static inline int ext4_handle_dirty_dx_node(handle_t *handle,
492 struct inode *inode,
493 struct buffer_head *bh)
494{
495 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
496 return ext4_handle_dirty_metadata(handle, inode, bh);
497}
498
499/*
500 * p is at least 6 bytes before the end of page
501 */
502static inline struct ext4_dir_entry_2 *
503ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
504{
505 return (struct ext4_dir_entry_2 *)((char *)p +
506 ext4_rec_len_from_disk(p->rec_len, blocksize));
507}
508
509/*
510 * Future: use high four bits of block for coalesce-on-delete flags
511 * Mask them off for now.
512 */
513
514static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
515{
516 return le32_to_cpu(entry->block) & 0x00ffffff;
517}
518
519static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
520{
521 entry->block = cpu_to_le32(value);
522}
523
524static inline unsigned dx_get_hash(struct dx_entry *entry)
525{
526 return le32_to_cpu(entry->hash);
527}
528
529static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
530{
531 entry->hash = cpu_to_le32(value);
532}
533
534static inline unsigned dx_get_count(struct dx_entry *entries)
535{
536 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
537}
538
539static inline unsigned dx_get_limit(struct dx_entry *entries)
540{
541 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
542}
543
544static inline void dx_set_count(struct dx_entry *entries, unsigned value)
545{
546 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
547}
548
549static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
550{
551 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
552}
553
554static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
555{
556 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
557 EXT4_DIR_REC_LEN(2) - infosize;
558
559 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
560 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
561 entry_space -= sizeof(struct dx_tail);
562 return entry_space / sizeof(struct dx_entry);
563}
564
565static inline unsigned dx_node_limit(struct inode *dir)
566{
567 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
568
569 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
570 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
571 entry_space -= sizeof(struct dx_tail);
572 return entry_space / sizeof(struct dx_entry);
573}
574
575/*
576 * Debug
577 */
578#ifdef DX_DEBUG
579static void dx_show_index(char * label, struct dx_entry *entries)
580{
581 int i, n = dx_get_count (entries);
582 printk(KERN_DEBUG "%s index ", label);
583 for (i = 0; i < n; i++) {
584 printk("%x->%lu ", i ? dx_get_hash(entries + i) :
585 0, (unsigned long)dx_get_block(entries + i));
586 }
587 printk("\n");
588}
589
590struct stats
591{
592 unsigned names;
593 unsigned space;
594 unsigned bcount;
595};
596
597static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
598 int size, int show_names)
599{
600 unsigned names = 0, space = 0;
601 char *base = (char *) de;
602 struct dx_hash_info h = *hinfo;
603
604 printk("names: ");
605 while ((char *) de < base + size)
606 {
607 if (de->inode)
608 {
609 if (show_names)
610 {
611 int len = de->name_len;
612 char *name = de->name;
613 while (len--) printk("%c", *name++);
614 ext4fs_dirhash(de->name, de->name_len, &h);
615 printk(":%x.%u ", h.hash,
616 (unsigned) ((char *) de - base));
617 }
618 space += EXT4_DIR_REC_LEN(de->name_len);
619 names++;
620 }
621 de = ext4_next_entry(de, size);
622 }
623 printk("(%i)\n", names);
624 return (struct stats) { names, space, 1 };
625}
626
627struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
628 struct dx_entry *entries, int levels)
629{
630 unsigned blocksize = dir->i_sb->s_blocksize;
631 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
632 unsigned bcount = 0;
633 struct buffer_head *bh;
634 int err;
635 printk("%i indexed blocks...\n", count);
636 for (i = 0; i < count; i++, entries++)
637 {
638 ext4_lblk_t block = dx_get_block(entries);
639 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
640 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
641 struct stats stats;
642 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
643 if (!(bh = ext4_bread (NULL,dir, block, 0,&err))) continue;
644 stats = levels?
645 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
646 dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
647 names += stats.names;
648 space += stats.space;
649 bcount += stats.bcount;
650 brelse(bh);
651 }
652 if (bcount)
653 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
654 levels ? "" : " ", names, space/bcount,
655 (space/bcount)*100/blocksize);
656 return (struct stats) { names, space, bcount};
657}
658#endif /* DX_DEBUG */
659
660/*
661 * Probe for a directory leaf block to search.
662 *
663 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
664 * error in the directory index, and the caller should fall back to
665 * searching the directory normally. The callers of dx_probe **MUST**
666 * check for this error code, and make sure it never gets reflected
667 * back to userspace.
668 */
669static struct dx_frame *
670dx_probe(const struct qstr *d_name, struct inode *dir,
671 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
672{
673 unsigned count, indirect;
674 struct dx_entry *at, *entries, *p, *q, *m;
675 struct dx_root *root;
676 struct buffer_head *bh;
677 struct dx_frame *frame = frame_in;
678 u32 hash;
679
680 frame->bh = NULL;
681 bh = ext4_read_dirblock(dir, 0, INDEX);
682 if (IS_ERR(bh)) {
683 *err = PTR_ERR(bh);
684 goto fail;
685 }
686 root = (struct dx_root *) bh->b_data;
687 if (root->info.hash_version != DX_HASH_TEA &&
688 root->info.hash_version != DX_HASH_HALF_MD4 &&
689 root->info.hash_version != DX_HASH_LEGACY) {
690 ext4_warning(dir->i_sb, "Unrecognised inode hash code %d",
691 root->info.hash_version);
692 brelse(bh);
693 *err = ERR_BAD_DX_DIR;
694 goto fail;
695 }
696 hinfo->hash_version = root->info.hash_version;
697 if (hinfo->hash_version <= DX_HASH_TEA)
698 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
699 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
700 if (d_name)
701 ext4fs_dirhash(d_name->name, d_name->len, hinfo);
702 hash = hinfo->hash;
703
704 if (root->info.unused_flags & 1) {
705 ext4_warning(dir->i_sb, "Unimplemented inode hash flags: %#06x",
706 root->info.unused_flags);
707 brelse(bh);
708 *err = ERR_BAD_DX_DIR;
709 goto fail;
710 }
711
712 if ((indirect = root->info.indirect_levels) > 1) {
713 ext4_warning(dir->i_sb, "Unimplemented inode hash depth: %#06x",
714 root->info.indirect_levels);
715 brelse(bh);
716 *err = ERR_BAD_DX_DIR;
717 goto fail;
718 }
719
720 entries = (struct dx_entry *) (((char *)&root->info) +
721 root->info.info_length);
722
723 if (dx_get_limit(entries) != dx_root_limit(dir,
724 root->info.info_length)) {
725 ext4_warning(dir->i_sb, "dx entry: limit != root limit");
726 brelse(bh);
727 *err = ERR_BAD_DX_DIR;
728 goto fail;
729 }
730
731 dxtrace(printk("Look up %x", hash));
732 while (1)
733 {
734 count = dx_get_count(entries);
735 if (!count || count > dx_get_limit(entries)) {
736 ext4_warning(dir->i_sb,
737 "dx entry: no count or count > limit");
738 brelse(bh);
739 *err = ERR_BAD_DX_DIR;
740 goto fail2;
741 }
742
743 p = entries + 1;
744 q = entries + count - 1;
745 while (p <= q)
746 {
747 m = p + (q - p)/2;
748 dxtrace(printk("."));
749 if (dx_get_hash(m) > hash)
750 q = m - 1;
751 else
752 p = m + 1;
753 }
754
755 if (0) // linear search cross check
756 {
757 unsigned n = count - 1;
758 at = entries;
759 while (n--)
760 {
761 dxtrace(printk(","));
762 if (dx_get_hash(++at) > hash)
763 {
764 at--;
765 break;
766 }
767 }
768 assert (at == p - 1);
769 }
770
771 at = p - 1;
772 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
773 frame->bh = bh;
774 frame->entries = entries;
775 frame->at = at;
776 if (!indirect--) return frame;
777 bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
778 if (IS_ERR(bh)) {
779 *err = PTR_ERR(bh);
780 goto fail2;
781 }
782 entries = ((struct dx_node *) bh->b_data)->entries;
783
784 if (dx_get_limit(entries) != dx_node_limit (dir)) {
785 ext4_warning(dir->i_sb,
786 "dx entry: limit != node limit");
787 brelse(bh);
788 *err = ERR_BAD_DX_DIR;
789 goto fail2;
790 }
791 frame++;
792 frame->bh = NULL;
793 }
794fail2:
795 while (frame >= frame_in) {
796 brelse(frame->bh);
797 frame--;
798 }
799fail:
800 if (*err == ERR_BAD_DX_DIR)
801 ext4_warning(dir->i_sb,
802 "Corrupt dir inode %lu, running e2fsck is "
803 "recommended.", dir->i_ino);
804 return NULL;
805}
806
807static void dx_release (struct dx_frame *frames)
808{
809 if (frames[0].bh == NULL)
810 return;
811
812 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
813 brelse(frames[1].bh);
814 brelse(frames[0].bh);
815}
816
817/*
818 * This function increments the frame pointer to search the next leaf
819 * block, and reads in the necessary intervening nodes if the search
820 * should be necessary. Whether or not the search is necessary is
821 * controlled by the hash parameter. If the hash value is even, then
822 * the search is only continued if the next block starts with that
823 * hash value. This is used if we are searching for a specific file.
824 *
825 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
826 *
827 * This function returns 1 if the caller should continue to search,
828 * or 0 if it should not. If there is an error reading one of the
829 * index blocks, it will a negative error code.
830 *
831 * If start_hash is non-null, it will be filled in with the starting
832 * hash of the next page.
833 */
834static int ext4_htree_next_block(struct inode *dir, __u32 hash,
835 struct dx_frame *frame,
836 struct dx_frame *frames,
837 __u32 *start_hash)
838{
839 struct dx_frame *p;
840 struct buffer_head *bh;
841 int num_frames = 0;
842 __u32 bhash;
843
844 p = frame;
845 /*
846 * Find the next leaf page by incrementing the frame pointer.
847 * If we run out of entries in the interior node, loop around and
848 * increment pointer in the parent node. When we break out of
849 * this loop, num_frames indicates the number of interior
850 * nodes need to be read.
851 */
852 while (1) {
853 if (++(p->at) < p->entries + dx_get_count(p->entries))
854 break;
855 if (p == frames)
856 return 0;
857 num_frames++;
858 p--;
859 }
860
861 /*
862 * If the hash is 1, then continue only if the next page has a
863 * continuation hash of any value. This is used for readdir
864 * handling. Otherwise, check to see if the hash matches the
865 * desired contiuation hash. If it doesn't, return since
866 * there's no point to read in the successive index pages.
867 */
868 bhash = dx_get_hash(p->at);
869 if (start_hash)
870 *start_hash = bhash;
871 if ((hash & 1) == 0) {
872 if ((bhash & ~1) != hash)
873 return 0;
874 }
875 /*
876 * If the hash is HASH_NB_ALWAYS, we always go to the next
877 * block so no check is necessary
878 */
879 while (num_frames--) {
880 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
881 if (IS_ERR(bh))
882 return PTR_ERR(bh);
883 p++;
884 brelse(p->bh);
885 p->bh = bh;
886 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
887 }
888 return 1;
889}
890
891
892/*
893 * This function fills a red-black tree with information from a
894 * directory block. It returns the number directory entries loaded
895 * into the tree. If there is an error it is returned in err.
896 */
897static int htree_dirblock_to_tree(struct file *dir_file,
898 struct inode *dir, ext4_lblk_t block,
899 struct dx_hash_info *hinfo,
900 __u32 start_hash, __u32 start_minor_hash)
901{
902 struct buffer_head *bh;
903 struct ext4_dir_entry_2 *de, *top;
904 int err = 0, count = 0;
905
906 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
907 (unsigned long)block));
908 bh = ext4_read_dirblock(dir, block, DIRENT);
909 if (IS_ERR(bh))
910 return PTR_ERR(bh);
911
912 de = (struct ext4_dir_entry_2 *) bh->b_data;
913 top = (struct ext4_dir_entry_2 *) ((char *) de +
914 dir->i_sb->s_blocksize -
915 EXT4_DIR_REC_LEN(0));
916 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
917 if (ext4_check_dir_entry(dir, NULL, de, bh,
918 bh->b_data, bh->b_size,
919 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
920 + ((char *)de - bh->b_data))) {
921 /* silently ignore the rest of the block */
922 break;
923 }
924 ext4fs_dirhash(de->name, de->name_len, hinfo);
925 if ((hinfo->hash < start_hash) ||
926 ((hinfo->hash == start_hash) &&
927 (hinfo->minor_hash < start_minor_hash)))
928 continue;
929 if (de->inode == 0)
930 continue;
931 if ((err = ext4_htree_store_dirent(dir_file,
932 hinfo->hash, hinfo->minor_hash, de)) != 0) {
933 brelse(bh);
934 return err;
935 }
936 count++;
937 }
938 brelse(bh);
939 return count;
940}
941
942
943/*
944 * This function fills a red-black tree with information from a
945 * directory. We start scanning the directory in hash order, starting
946 * at start_hash and start_minor_hash.
947 *
948 * This function returns the number of entries inserted into the tree,
949 * or a negative error code.
950 */
951int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
952 __u32 start_minor_hash, __u32 *next_hash)
953{
954 struct dx_hash_info hinfo;
955 struct ext4_dir_entry_2 *de;
956 struct dx_frame frames[2], *frame;
957 struct inode *dir;
958 ext4_lblk_t block;
959 int count = 0;
960 int ret, err;
961 __u32 hashval;
962
963 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
964 start_hash, start_minor_hash));
965 dir = file_inode(dir_file);
966 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
967 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
968 if (hinfo.hash_version <= DX_HASH_TEA)
969 hinfo.hash_version +=
970 EXT4_SB(dir->i_sb)->s_hash_unsigned;
971 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
972 if (ext4_has_inline_data(dir)) {
973 int has_inline_data = 1;
974 count = htree_inlinedir_to_tree(dir_file, dir, 0,
975 &hinfo, start_hash,
976 start_minor_hash,
977 &has_inline_data);
978 if (has_inline_data) {
979 *next_hash = ~0;
980 return count;
981 }
982 }
983 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
984 start_hash, start_minor_hash);
985 *next_hash = ~0;
986 return count;
987 }
988 hinfo.hash = start_hash;
989 hinfo.minor_hash = 0;
990 frame = dx_probe(NULL, dir, &hinfo, frames, &err);
991 if (!frame)
992 return err;
993
994 /* Add '.' and '..' from the htree header */
995 if (!start_hash && !start_minor_hash) {
996 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
997 if ((err = ext4_htree_store_dirent(dir_file, 0, 0, de)) != 0)
998 goto errout;
999 count++;
1000 }
1001 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
1002 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1003 de = ext4_next_entry(de, dir->i_sb->s_blocksize);
1004 if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
1005 goto errout;
1006 count++;
1007 }
1008
1009 while (1) {
1010 block = dx_get_block(frame->at);
1011 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
1012 start_hash, start_minor_hash);
1013 if (ret < 0) {
1014 err = ret;
1015 goto errout;
1016 }
1017 count += ret;
1018 hashval = ~0;
1019 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
1020 frame, frames, &hashval);
1021 *next_hash = hashval;
1022 if (ret < 0) {
1023 err = ret;
1024 goto errout;
1025 }
1026 /*
1027 * Stop if: (a) there are no more entries, or
1028 * (b) we have inserted at least one entry and the
1029 * next hash value is not a continuation
1030 */
1031 if ((ret == 0) ||
1032 (count && ((hashval & 1) == 0)))
1033 break;
1034 }
1035 dx_release(frames);
1036 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1037 "next hash: %x\n", count, *next_hash));
1038 return count;
1039errout:
1040 dx_release(frames);
1041 return (err);
1042}
1043
1044static inline int search_dirblock(struct buffer_head *bh,
1045 struct inode *dir,
1046 const struct qstr *d_name,
1047 unsigned int offset,
1048 struct ext4_dir_entry_2 **res_dir)
1049{
1050 return search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,
1051 d_name, offset, res_dir);
1052}
1053
1054/*
1055 * Directory block splitting, compacting
1056 */
1057
1058/*
1059 * Create map of hash values, offsets, and sizes, stored at end of block.
1060 * Returns number of entries mapped.
1061 */
1062static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
1063 struct dx_hash_info *hinfo,
1064 struct dx_map_entry *map_tail)
1065{
1066 int count = 0;
1067 char *base = (char *) de;
1068 struct dx_hash_info h = *hinfo;
1069
1070 while ((char *) de < base + blocksize) {
1071 if (de->name_len && de->inode) {
1072 ext4fs_dirhash(de->name, de->name_len, &h);
1073 map_tail--;
1074 map_tail->hash = h.hash;
1075 map_tail->offs = ((char *) de - base)>>2;
1076 map_tail->size = le16_to_cpu(de->rec_len);
1077 count++;
1078 cond_resched();
1079 }
1080 /* XXX: do we need to check rec_len == 0 case? -Chris */
1081 de = ext4_next_entry(de, blocksize);
1082 }
1083 return count;
1084}
1085
1086/* Sort map by hash value */
1087static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1088{
1089 struct dx_map_entry *p, *q, *top = map + count - 1;
1090 int more;
1091 /* Combsort until bubble sort doesn't suck */
1092 while (count > 2) {
1093 count = count*10/13;
1094 if (count - 9 < 2) /* 9, 10 -> 11 */
1095 count = 11;
1096 for (p = top, q = p - count; q >= map; p--, q--)
1097 if (p->hash < q->hash)
1098 swap(*p, *q);
1099 }
1100 /* Garden variety bubble sort */
1101 do {
1102 more = 0;
1103 q = top;
1104 while (q-- > map) {
1105 if (q[1].hash >= q[0].hash)
1106 continue;
1107 swap(*(q+1), *q);
1108 more = 1;
1109 }
1110 } while(more);
1111}
1112
1113static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
1114{
1115 struct dx_entry *entries = frame->entries;
1116 struct dx_entry *old = frame->at, *new = old + 1;
1117 int count = dx_get_count(entries);
1118
1119 assert(count < dx_get_limit(entries));
1120 assert(old < entries + count);
1121 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1122 dx_set_hash(new, hash);
1123 dx_set_block(new, block);
1124 dx_set_count(entries, count + 1);
1125}
1126
1127/*
1128 * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
1129 *
1130 * `len <= EXT4_NAME_LEN' is guaranteed by caller.
1131 * `de != NULL' is guaranteed by caller.
1132 */
1133static inline int ext4_match (int len, const char * const name,
1134 struct ext4_dir_entry_2 * de)
1135{
1136 if (len != de->name_len)
1137 return 0;
1138 if (!de->inode)
1139 return 0;
1140 return !memcmp(name, de->name, len);
1141}
1142
1143/*
1144 * Returns 0 if not found, -1 on failure, and 1 on success
1145 */
1146int search_dir(struct buffer_head *bh,
1147 char *search_buf,
1148 int buf_size,
1149 struct inode *dir,
1150 const struct qstr *d_name,
1151 unsigned int offset,
1152 struct ext4_dir_entry_2 **res_dir)
1153{
1154 struct ext4_dir_entry_2 * de;
1155 char * dlimit;
1156 int de_len;
1157 const char *name = d_name->name;
1158 int namelen = d_name->len;
1159
1160 de = (struct ext4_dir_entry_2 *)search_buf;
1161 dlimit = search_buf + buf_size;
1162 while ((char *) de < dlimit) {
1163 /* this code is executed quadratically often */
1164 /* do minimal checking `by hand' */
1165
1166 if ((char *) de + namelen <= dlimit &&
1167 ext4_match (namelen, name, de)) {
1168 /* found a match - just to be sure, do a full check */
1169 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
1170 bh->b_size, offset))
1171 return -1;
1172 *res_dir = de;
1173 return 1;
1174 }
1175 /* prevent looping on a bad block */
1176 de_len = ext4_rec_len_from_disk(de->rec_len,
1177 dir->i_sb->s_blocksize);
1178 if (de_len <= 0)
1179 return -1;
1180 offset += de_len;
1181 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1182 }
1183 return 0;
1184}
1185
1186static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1187 struct ext4_dir_entry *de)
1188{
1189 struct super_block *sb = dir->i_sb;
1190
1191 if (!is_dx(dir))
1192 return 0;
1193 if (block == 0)
1194 return 1;
1195 if (de->inode == 0 &&
1196 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
1197 sb->s_blocksize)
1198 return 1;
1199 return 0;
1200}
1201
1202/*
1203 * ext4_find_entry()
1204 *
1205 * finds an entry in the specified directory with the wanted name. It
1206 * returns the cache buffer in which the entry was found, and the entry
1207 * itself (as a parameter - res_dir). It does NOT read the inode of the
1208 * entry - you'll have to do that yourself if you want to.
1209 *
1210 * The returned buffer_head has ->b_count elevated. The caller is expected
1211 * to brelse() it when appropriate.
1212 */
1213static struct buffer_head * ext4_find_entry (struct inode *dir,
1214 const struct qstr *d_name,
1215 struct ext4_dir_entry_2 **res_dir,
1216 int *inlined)
1217{
1218 struct super_block *sb;
1219 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1220 struct buffer_head *bh, *ret = NULL;
1221 ext4_lblk_t start, block, b;
1222 const u8 *name = d_name->name;
1223 int ra_max = 0; /* Number of bh's in the readahead
1224 buffer, bh_use[] */
1225 int ra_ptr = 0; /* Current index into readahead
1226 buffer */
1227 int num = 0;
1228 ext4_lblk_t nblocks;
1229 int i, err;
1230 int namelen;
1231
1232 *res_dir = NULL;
1233 sb = dir->i_sb;
1234 namelen = d_name->len;
1235 if (namelen > EXT4_NAME_LEN)
1236 return NULL;
1237
1238 if (ext4_has_inline_data(dir)) {
1239 int has_inline_data = 1;
1240 ret = ext4_find_inline_entry(dir, d_name, res_dir,
1241 &has_inline_data);
1242 if (has_inline_data) {
1243 if (inlined)
1244 *inlined = 1;
1245 return ret;
1246 }
1247 }
1248
1249 if ((namelen <= 2) && (name[0] == '.') &&
1250 (name[1] == '.' || name[1] == '\0')) {
1251 /*
1252 * "." or ".." will only be in the first block
1253 * NFS may look up ".."; "." should be handled by the VFS
1254 */
1255 block = start = 0;
1256 nblocks = 1;
1257 goto restart;
1258 }
1259 if (is_dx(dir)) {
1260 bh = ext4_dx_find_entry(dir, d_name, res_dir, &err);
1261 /*
1262 * On success, or if the error was file not found,
1263 * return. Otherwise, fall back to doing a search the
1264 * old fashioned way.
1265 */
1266 if (bh || (err != ERR_BAD_DX_DIR))
1267 return bh;
1268 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1269 "falling back\n"));
1270 }
1271 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1272 start = EXT4_I(dir)->i_dir_start_lookup;
1273 if (start >= nblocks)
1274 start = 0;
1275 block = start;
1276restart:
1277 do {
1278 /*
1279 * We deal with the read-ahead logic here.
1280 */
1281 if (ra_ptr >= ra_max) {
1282 /* Refill the readahead buffer */
1283 ra_ptr = 0;
1284 b = block;
1285 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
1286 /*
1287 * Terminate if we reach the end of the
1288 * directory and must wrap, or if our
1289 * search has finished at this block.
1290 */
1291 if (b >= nblocks || (num && block == start)) {
1292 bh_use[ra_max] = NULL;
1293 break;
1294 }
1295 num++;
1296 bh = ext4_getblk(NULL, dir, b++, 0, &err);
1297 bh_use[ra_max] = bh;
1298 if (bh)
1299 ll_rw_block(READ | REQ_META | REQ_PRIO,
1300 1, &bh);
1301 }
1302 }
1303 if ((bh = bh_use[ra_ptr++]) == NULL)
1304 goto next;
1305 wait_on_buffer(bh);
1306 if (!buffer_uptodate(bh)) {
1307 /* read error, skip block & hope for the best */
1308 EXT4_ERROR_INODE(dir, "reading directory lblock %lu",
1309 (unsigned long) block);
1310 brelse(bh);
1311 goto next;
1312 }
1313 if (!buffer_verified(bh) &&
1314 !is_dx_internal_node(dir, block,
1315 (struct ext4_dir_entry *)bh->b_data) &&
1316 !ext4_dirent_csum_verify(dir,
1317 (struct ext4_dir_entry *)bh->b_data)) {
1318 EXT4_ERROR_INODE(dir, "checksumming directory "
1319 "block %lu", (unsigned long)block);
1320 brelse(bh);
1321 goto next;
1322 }
1323 set_buffer_verified(bh);
1324 i = search_dirblock(bh, dir, d_name,
1325 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
1326 if (i == 1) {
1327 EXT4_I(dir)->i_dir_start_lookup = block;
1328 ret = bh;
1329 goto cleanup_and_exit;
1330 } else {
1331 brelse(bh);
1332 if (i < 0)
1333 goto cleanup_and_exit;
1334 }
1335 next:
1336 if (++block >= nblocks)
1337 block = 0;
1338 } while (block != start);
1339
1340 /*
1341 * If the directory has grown while we were searching, then
1342 * search the last part of the directory before giving up.
1343 */
1344 block = nblocks;
1345 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1346 if (block < nblocks) {
1347 start = 0;
1348 goto restart;
1349 }
1350
1351cleanup_and_exit:
1352 /* Clean up the read-ahead blocks */
1353 for (; ra_ptr < ra_max; ra_ptr++)
1354 brelse(bh_use[ra_ptr]);
1355 return ret;
1356}
1357
1358static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct qstr *d_name,
1359 struct ext4_dir_entry_2 **res_dir, int *err)
1360{
1361 struct super_block * sb = dir->i_sb;
1362 struct dx_hash_info hinfo;
1363 struct dx_frame frames[2], *frame;
1364 struct buffer_head *bh;
1365 ext4_lblk_t block;
1366 int retval;
1367
1368 if (!(frame = dx_probe(d_name, dir, &hinfo, frames, err)))
1369 return NULL;
1370 do {
1371 block = dx_get_block(frame->at);
1372 bh = ext4_read_dirblock(dir, block, DIRENT);
1373 if (IS_ERR(bh)) {
1374 *err = PTR_ERR(bh);
1375 goto errout;
1376 }
1377 retval = search_dirblock(bh, dir, d_name,
1378 block << EXT4_BLOCK_SIZE_BITS(sb),
1379 res_dir);
1380 if (retval == 1) { /* Success! */
1381 dx_release(frames);
1382 return bh;
1383 }
1384 brelse(bh);
1385 if (retval == -1) {
1386 *err = ERR_BAD_DX_DIR;
1387 goto errout;
1388 }
1389
1390 /* Check to see if we should continue to search */
1391 retval = ext4_htree_next_block(dir, hinfo.hash, frame,
1392 frames, NULL);
1393 if (retval < 0) {
1394 ext4_warning(sb,
1395 "error reading index page in directory #%lu",
1396 dir->i_ino);
1397 *err = retval;
1398 goto errout;
1399 }
1400 } while (retval == 1);
1401
1402 *err = -ENOENT;
1403errout:
1404 dxtrace(printk(KERN_DEBUG "%s not found\n", d_name->name));
1405 dx_release (frames);
1406 return NULL;
1407}
1408
1409static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
1410{
1411 struct inode *inode;
1412 struct ext4_dir_entry_2 *de;
1413 struct buffer_head *bh;
1414
1415 if (dentry->d_name.len > EXT4_NAME_LEN)
1416 return ERR_PTR(-ENAMETOOLONG);
1417
1418 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
1419 inode = NULL;
1420 if (bh) {
1421 __u32 ino = le32_to_cpu(de->inode);
1422 brelse(bh);
1423 if (!ext4_valid_inum(dir->i_sb, ino)) {
1424 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1425 return ERR_PTR(-EIO);
1426 }
1427 if (unlikely(ino == dir->i_ino)) {
1428 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
1429 dentry);
1430 return ERR_PTR(-EIO);
1431 }
1432 inode = ext4_iget(dir->i_sb, ino);
1433 if (inode == ERR_PTR(-ESTALE)) {
1434 EXT4_ERROR_INODE(dir,
1435 "deleted inode referenced: %u",
1436 ino);
1437 return ERR_PTR(-EIO);
1438 }
1439 }
1440 return d_splice_alias(inode, dentry);
1441}
1442
1443
1444struct dentry *ext4_get_parent(struct dentry *child)
1445{
1446 __u32 ino;
1447 static const struct qstr dotdot = QSTR_INIT("..", 2);
1448 struct ext4_dir_entry_2 * de;
1449 struct buffer_head *bh;
1450
1451 bh = ext4_find_entry(child->d_inode, &dotdot, &de, NULL);
1452 if (!bh)
1453 return ERR_PTR(-ENOENT);
1454 ino = le32_to_cpu(de->inode);
1455 brelse(bh);
1456
1457 if (!ext4_valid_inum(child->d_inode->i_sb, ino)) {
1458 EXT4_ERROR_INODE(child->d_inode,
1459 "bad parent inode number: %u", ino);
1460 return ERR_PTR(-EIO);
1461 }
1462
1463 return d_obtain_alias(ext4_iget(child->d_inode->i_sb, ino));
1464}
1465
1466/*
1467 * Move count entries from end of map between two memory locations.
1468 * Returns pointer to last entry moved.
1469 */
1470static struct ext4_dir_entry_2 *
1471dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1472 unsigned blocksize)
1473{
1474 unsigned rec_len = 0;
1475
1476 while (count--) {
1477 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
1478 (from + (map->offs<<2));
1479 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1480 memcpy (to, de, rec_len);
1481 ((struct ext4_dir_entry_2 *) to)->rec_len =
1482 ext4_rec_len_to_disk(rec_len, blocksize);
1483 de->inode = 0;
1484 map++;
1485 to += rec_len;
1486 }
1487 return (struct ext4_dir_entry_2 *) (to - rec_len);
1488}
1489
1490/*
1491 * Compact each dir entry in the range to the minimal rec_len.
1492 * Returns pointer to last entry in range.
1493 */
1494static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
1495{
1496 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
1497 unsigned rec_len = 0;
1498
1499 prev = to = de;
1500 while ((char*)de < base + blocksize) {
1501 next = ext4_next_entry(de, blocksize);
1502 if (de->inode && de->name_len) {
1503 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1504 if (de > to)
1505 memmove(to, de, rec_len);
1506 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
1507 prev = to;
1508 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
1509 }
1510 de = next;
1511 }
1512 return prev;
1513}
1514
1515/*
1516 * Split a full leaf block to make room for a new dir entry.
1517 * Allocate a new block, and move entries so that they are approx. equally full.
1518 * Returns pointer to de in block into which the new entry will be inserted.
1519 */
1520static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1521 struct buffer_head **bh,struct dx_frame *frame,
1522 struct dx_hash_info *hinfo, int *error)
1523{
1524 unsigned blocksize = dir->i_sb->s_blocksize;
1525 unsigned count, continued;
1526 struct buffer_head *bh2;
1527 ext4_lblk_t newblock;
1528 u32 hash2;
1529 struct dx_map_entry *map;
1530 char *data1 = (*bh)->b_data, *data2;
1531 unsigned split, move, size;
1532 struct ext4_dir_entry_2 *de = NULL, *de2;
1533 struct ext4_dir_entry_tail *t;
1534 int csum_size = 0;
1535 int err = 0, i;
1536
1537 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
1538 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1539 csum_size = sizeof(struct ext4_dir_entry_tail);
1540
1541 bh2 = ext4_append(handle, dir, &newblock);
1542 if (IS_ERR(bh2)) {
1543 brelse(*bh);
1544 *bh = NULL;
1545 *error = PTR_ERR(bh2);
1546 return NULL;
1547 }
1548
1549 BUFFER_TRACE(*bh, "get_write_access");
1550 err = ext4_journal_get_write_access(handle, *bh);
1551 if (err)
1552 goto journal_error;
1553
1554 BUFFER_TRACE(frame->bh, "get_write_access");
1555 err = ext4_journal_get_write_access(handle, frame->bh);
1556 if (err)
1557 goto journal_error;
1558
1559 data2 = bh2->b_data;
1560
1561 /* create map in the end of data2 block */
1562 map = (struct dx_map_entry *) (data2 + blocksize);
1563 count = dx_make_map((struct ext4_dir_entry_2 *) data1,
1564 blocksize, hinfo, map);
1565 map -= count;
1566 dx_sort_map(map, count);
1567 /* Split the existing block in the middle, size-wise */
1568 size = 0;
1569 move = 0;
1570 for (i = count-1; i >= 0; i--) {
1571 /* is more than half of this entry in 2nd half of the block? */
1572 if (size + map[i].size/2 > blocksize/2)
1573 break;
1574 size += map[i].size;
1575 move++;
1576 }
1577 /* map index at which we will split */
1578 split = count - move;
1579 hash2 = map[split].hash;
1580 continued = hash2 == map[split - 1].hash;
1581 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1582 (unsigned long)dx_get_block(frame->at),
1583 hash2, split, count-split));
1584
1585 /* Fancy dance to stay within two buffers */
1586 de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize);
1587 de = dx_pack_dirents(data1, blocksize);
1588 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1589 (char *) de,
1590 blocksize);
1591 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1592 (char *) de2,
1593 blocksize);
1594 if (csum_size) {
1595 t = EXT4_DIRENT_TAIL(data2, blocksize);
1596 initialize_dirent_tail(t, blocksize);
1597
1598 t = EXT4_DIRENT_TAIL(data1, blocksize);
1599 initialize_dirent_tail(t, blocksize);
1600 }
1601
1602 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
1603 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
1604
1605 /* Which block gets the new entry? */
1606 if (hinfo->hash >= hash2)
1607 {
1608 swap(*bh, bh2);
1609 de = de2;
1610 }
1611 dx_insert_block(frame, hash2 + continued, newblock);
1612 err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
1613 if (err)
1614 goto journal_error;
1615 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1616 if (err)
1617 goto journal_error;
1618 brelse(bh2);
1619 dxtrace(dx_show_index("frame", frame->entries));
1620 return de;
1621
1622journal_error:
1623 brelse(*bh);
1624 brelse(bh2);
1625 *bh = NULL;
1626 ext4_std_error(dir->i_sb, err);
1627 *error = err;
1628 return NULL;
1629}
1630
1631int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1632 struct buffer_head *bh,
1633 void *buf, int buf_size,
1634 const char *name, int namelen,
1635 struct ext4_dir_entry_2 **dest_de)
1636{
1637 struct ext4_dir_entry_2 *de;
1638 unsigned short reclen = EXT4_DIR_REC_LEN(namelen);
1639 int nlen, rlen;
1640 unsigned int offset = 0;
1641 char *top;
1642
1643 de = (struct ext4_dir_entry_2 *)buf;
1644 top = buf + buf_size - reclen;
1645 while ((char *) de <= top) {
1646 if (ext4_check_dir_entry(dir, NULL, de, bh,
1647 buf, buf_size, offset))
1648 return -EIO;
1649 if (ext4_match(namelen, name, de))
1650 return -EEXIST;
1651 nlen = EXT4_DIR_REC_LEN(de->name_len);
1652 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1653 if ((de->inode ? rlen - nlen : rlen) >= reclen)
1654 break;
1655 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1656 offset += rlen;
1657 }
1658 if ((char *) de > top)
1659 return -ENOSPC;
1660
1661 *dest_de = de;
1662 return 0;
1663}
1664
1665void ext4_insert_dentry(struct inode *inode,
1666 struct ext4_dir_entry_2 *de,
1667 int buf_size,
1668 const char *name, int namelen)
1669{
1670
1671 int nlen, rlen;
1672
1673 nlen = EXT4_DIR_REC_LEN(de->name_len);
1674 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1675 if (de->inode) {
1676 struct ext4_dir_entry_2 *de1 =
1677 (struct ext4_dir_entry_2 *)((char *)de + nlen);
1678 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
1679 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
1680 de = de1;
1681 }
1682 de->file_type = EXT4_FT_UNKNOWN;
1683 de->inode = cpu_to_le32(inode->i_ino);
1684 ext4_set_de_type(inode->i_sb, de, inode->i_mode);
1685 de->name_len = namelen;
1686 memcpy(de->name, name, namelen);
1687}
1688/*
1689 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1690 * it points to a directory entry which is guaranteed to be large
1691 * enough for new directory entry. If de is NULL, then
1692 * add_dirent_to_buf will attempt search the directory block for
1693 * space. It will return -ENOSPC if no space is available, and -EIO
1694 * and -EEXIST if directory entry already exists.
1695 */
1696static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
1697 struct inode *inode, struct ext4_dir_entry_2 *de,
1698 struct buffer_head *bh)
1699{
1700 struct inode *dir = dentry->d_parent->d_inode;
1701 const char *name = dentry->d_name.name;
1702 int namelen = dentry->d_name.len;
1703 unsigned int blocksize = dir->i_sb->s_blocksize;
1704 int csum_size = 0;
1705 int err;
1706
1707 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1708 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1709 csum_size = sizeof(struct ext4_dir_entry_tail);
1710
1711 if (!de) {
1712 err = ext4_find_dest_de(dir, inode,
1713 bh, bh->b_data, blocksize - csum_size,
1714 name, namelen, &de);
1715 if (err)
1716 return err;
1717 }
1718 BUFFER_TRACE(bh, "get_write_access");
1719 err = ext4_journal_get_write_access(handle, bh);
1720 if (err) {
1721 ext4_std_error(dir->i_sb, err);
1722 return err;
1723 }
1724
1725 /* By now the buffer is marked for journaling */
1726 ext4_insert_dentry(inode, de, blocksize, name, namelen);
1727
1728 /*
1729 * XXX shouldn't update any times until successful
1730 * completion of syscall, but too many callers depend
1731 * on this.
1732 *
1733 * XXX similarly, too many callers depend on
1734 * ext4_new_inode() setting the times, but error
1735 * recovery deletes the inode, so the worst that can
1736 * happen is that the times are slightly out of date
1737 * and/or different from the directory change time.
1738 */
1739 dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
1740 ext4_update_dx_flag(dir);
1741 dir->i_version++;
1742 ext4_mark_inode_dirty(handle, dir);
1743 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
1744 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
1745 if (err)
1746 ext4_std_error(dir->i_sb, err);
1747 return 0;
1748}
1749
1750/*
1751 * This converts a one block unindexed directory to a 3 block indexed
1752 * directory, and adds the dentry to the indexed directory.
1753 */
1754static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1755 struct inode *inode, struct buffer_head *bh)
1756{
1757 struct inode *dir = dentry->d_parent->d_inode;
1758 const char *name = dentry->d_name.name;
1759 int namelen = dentry->d_name.len;
1760 struct buffer_head *bh2;
1761 struct dx_root *root;
1762 struct dx_frame frames[2], *frame;
1763 struct dx_entry *entries;
1764 struct ext4_dir_entry_2 *de, *de2;
1765 struct ext4_dir_entry_tail *t;
1766 char *data1, *top;
1767 unsigned len;
1768 int retval;
1769 unsigned blocksize;
1770 struct dx_hash_info hinfo;
1771 ext4_lblk_t block;
1772 struct fake_dirent *fde;
1773 int csum_size = 0;
1774
1775 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1776 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1777 csum_size = sizeof(struct ext4_dir_entry_tail);
1778
1779 blocksize = dir->i_sb->s_blocksize;
1780 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
1781 retval = ext4_journal_get_write_access(handle, bh);
1782 if (retval) {
1783 ext4_std_error(dir->i_sb, retval);
1784 brelse(bh);
1785 return retval;
1786 }
1787 root = (struct dx_root *) bh->b_data;
1788
1789 /* The 0th block becomes the root, move the dirents out */
1790 fde = &root->dotdot;
1791 de = (struct ext4_dir_entry_2 *)((char *)fde +
1792 ext4_rec_len_from_disk(fde->rec_len, blocksize));
1793 if ((char *) de >= (((char *) root) + blocksize)) {
1794 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
1795 brelse(bh);
1796 return -EIO;
1797 }
1798 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
1799
1800 /* Allocate new block for the 0th block's dirents */
1801 bh2 = ext4_append(handle, dir, &block);
1802 if (IS_ERR(bh2)) {
1803 brelse(bh);
1804 return PTR_ERR(bh2);
1805 }
1806 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
1807 data1 = bh2->b_data;
1808
1809 memcpy (data1, de, len);
1810 de = (struct ext4_dir_entry_2 *) data1;
1811 top = data1 + len;
1812 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
1813 de = de2;
1814 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1815 (char *) de,
1816 blocksize);
1817
1818 if (csum_size) {
1819 t = EXT4_DIRENT_TAIL(data1, blocksize);
1820 initialize_dirent_tail(t, blocksize);
1821 }
1822
1823 /* Initialize the root; the dot dirents already exist */
1824 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
1825 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
1826 blocksize);
1827 memset (&root->info, 0, sizeof(root->info));
1828 root->info.info_length = sizeof(root->info);
1829 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
1830 entries = root->entries;
1831 dx_set_block(entries, 1);
1832 dx_set_count(entries, 1);
1833 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
1834
1835 /* Initialize as for dx_probe */
1836 hinfo.hash_version = root->info.hash_version;
1837 if (hinfo.hash_version <= DX_HASH_TEA)
1838 hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
1839 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1840 ext4fs_dirhash(name, namelen, &hinfo);
1841 frame = frames;
1842 frame->entries = entries;
1843 frame->at = entries;
1844 frame->bh = bh;
1845 bh = bh2;
1846
1847 ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1848 ext4_handle_dirty_dirent_node(handle, dir, bh);
1849
1850 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
1851 if (!de) {
1852 /*
1853 * Even if the block split failed, we have to properly write
1854 * out all the changes we did so far. Otherwise we can end up
1855 * with corrupted filesystem.
1856 */
1857 ext4_mark_inode_dirty(handle, dir);
1858 dx_release(frames);
1859 return retval;
1860 }
1861 dx_release(frames);
1862
1863 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1864 brelse(bh);
1865 return retval;
1866}
1867
1868/*
1869 * ext4_add_entry()
1870 *
1871 * adds a file entry to the specified directory, using the same
1872 * semantics as ext4_find_entry(). It returns NULL if it failed.
1873 *
1874 * NOTE!! The inode part of 'de' is left at 0 - which means you
1875 * may not sleep between calling this and putting something into
1876 * the entry, as someone else might have used it while you slept.
1877 */
1878static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
1879 struct inode *inode)
1880{
1881 struct inode *dir = dentry->d_parent->d_inode;
1882 struct buffer_head *bh;
1883 struct ext4_dir_entry_2 *de;
1884 struct ext4_dir_entry_tail *t;
1885 struct super_block *sb;
1886 int retval;
1887 int dx_fallback=0;
1888 unsigned blocksize;
1889 ext4_lblk_t block, blocks;
1890 int csum_size = 0;
1891
1892 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1893 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1894 csum_size = sizeof(struct ext4_dir_entry_tail);
1895
1896 sb = dir->i_sb;
1897 blocksize = sb->s_blocksize;
1898 if (!dentry->d_name.len)
1899 return -EINVAL;
1900
1901 if (ext4_has_inline_data(dir)) {
1902 retval = ext4_try_add_inline_entry(handle, dentry, inode);
1903 if (retval < 0)
1904 return retval;
1905 if (retval == 1) {
1906 retval = 0;
1907 return retval;
1908 }
1909 }
1910
1911 if (is_dx(dir)) {
1912 retval = ext4_dx_add_entry(handle, dentry, inode);
1913 if (!retval || (retval != ERR_BAD_DX_DIR))
1914 return retval;
1915 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
1916 dx_fallback++;
1917 ext4_mark_inode_dirty(handle, dir);
1918 }
1919 blocks = dir->i_size >> sb->s_blocksize_bits;
1920 for (block = 0; block < blocks; block++) {
1921 bh = ext4_read_dirblock(dir, block, DIRENT);
1922 if (IS_ERR(bh))
1923 return PTR_ERR(bh);
1924
1925 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1926 if (retval != -ENOSPC) {
1927 brelse(bh);
1928 return retval;
1929 }
1930
1931 if (blocks == 1 && !dx_fallback &&
1932 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
1933 return make_indexed_dir(handle, dentry, inode, bh);
1934 brelse(bh);
1935 }
1936 bh = ext4_append(handle, dir, &block);
1937 if (IS_ERR(bh))
1938 return PTR_ERR(bh);
1939 de = (struct ext4_dir_entry_2 *) bh->b_data;
1940 de->inode = 0;
1941 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
1942
1943 if (csum_size) {
1944 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
1945 initialize_dirent_tail(t, blocksize);
1946 }
1947
1948 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1949 brelse(bh);
1950 if (retval == 0)
1951 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
1952 return retval;
1953}
1954
1955/*
1956 * Returns 0 for success, or a negative error value
1957 */
1958static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
1959 struct inode *inode)
1960{
1961 struct dx_frame frames[2], *frame;
1962 struct dx_entry *entries, *at;
1963 struct dx_hash_info hinfo;
1964 struct buffer_head *bh;
1965 struct inode *dir = dentry->d_parent->d_inode;
1966 struct super_block *sb = dir->i_sb;
1967 struct ext4_dir_entry_2 *de;
1968 int err;
1969
1970 frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err);
1971 if (!frame)
1972 return err;
1973 entries = frame->entries;
1974 at = frame->at;
1975 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT);
1976 if (IS_ERR(bh)) {
1977 err = PTR_ERR(bh);
1978 bh = NULL;
1979 goto cleanup;
1980 }
1981
1982 BUFFER_TRACE(bh, "get_write_access");
1983 err = ext4_journal_get_write_access(handle, bh);
1984 if (err)
1985 goto journal_error;
1986
1987 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1988 if (err != -ENOSPC)
1989 goto cleanup;
1990
1991 /* Block full, should compress but for now just split */
1992 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
1993 dx_get_count(entries), dx_get_limit(entries)));
1994 /* Need to split index? */
1995 if (dx_get_count(entries) == dx_get_limit(entries)) {
1996 ext4_lblk_t newblock;
1997 unsigned icount = dx_get_count(entries);
1998 int levels = frame - frames;
1999 struct dx_entry *entries2;
2000 struct dx_node *node2;
2001 struct buffer_head *bh2;
2002
2003 if (levels && (dx_get_count(frames->entries) ==
2004 dx_get_limit(frames->entries))) {
2005 ext4_warning(sb, "Directory index full!");
2006 err = -ENOSPC;
2007 goto cleanup;
2008 }
2009 bh2 = ext4_append(handle, dir, &newblock);
2010 if (IS_ERR(bh2)) {
2011 err = PTR_ERR(bh2);
2012 goto cleanup;
2013 }
2014 node2 = (struct dx_node *)(bh2->b_data);
2015 entries2 = node2->entries;
2016 memset(&node2->fake, 0, sizeof(struct fake_dirent));
2017 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
2018 sb->s_blocksize);
2019 BUFFER_TRACE(frame->bh, "get_write_access");
2020 err = ext4_journal_get_write_access(handle, frame->bh);
2021 if (err)
2022 goto journal_error;
2023 if (levels) {
2024 unsigned icount1 = icount/2, icount2 = icount - icount1;
2025 unsigned hash2 = dx_get_hash(entries + icount1);
2026 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2027 icount1, icount2));
2028
2029 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
2030 err = ext4_journal_get_write_access(handle,
2031 frames[0].bh);
2032 if (err)
2033 goto journal_error;
2034
2035 memcpy((char *) entries2, (char *) (entries + icount1),
2036 icount2 * sizeof(struct dx_entry));
2037 dx_set_count(entries, icount1);
2038 dx_set_count(entries2, icount2);
2039 dx_set_limit(entries2, dx_node_limit(dir));
2040
2041 /* Which index block gets the new entry? */
2042 if (at - entries >= icount1) {
2043 frame->at = at = at - entries - icount1 + entries2;
2044 frame->entries = entries = entries2;
2045 swap(frame->bh, bh2);
2046 }
2047 dx_insert_block(frames + 0, hash2, newblock);
2048 dxtrace(dx_show_index("node", frames[1].entries));
2049 dxtrace(dx_show_index("node",
2050 ((struct dx_node *) bh2->b_data)->entries));
2051 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2052 if (err)
2053 goto journal_error;
2054 brelse (bh2);
2055 } else {
2056 dxtrace(printk(KERN_DEBUG
2057 "Creating second level index...\n"));
2058 memcpy((char *) entries2, (char *) entries,
2059 icount * sizeof(struct dx_entry));
2060 dx_set_limit(entries2, dx_node_limit(dir));
2061
2062 /* Set up root */
2063 dx_set_count(entries, 1);
2064 dx_set_block(entries + 0, newblock);
2065 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
2066
2067 /* Add new access path frame */
2068 frame = frames + 1;
2069 frame->at = at = at - entries + entries2;
2070 frame->entries = entries = entries2;
2071 frame->bh = bh2;
2072 err = ext4_journal_get_write_access(handle,
2073 frame->bh);
2074 if (err)
2075 goto journal_error;
2076 }
2077 err = ext4_handle_dirty_dx_node(handle, dir, frames[0].bh);
2078 if (err) {
2079 ext4_std_error(inode->i_sb, err);
2080 goto cleanup;
2081 }
2082 }
2083 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
2084 if (!de)
2085 goto cleanup;
2086 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
2087 goto cleanup;
2088
2089journal_error:
2090 ext4_std_error(dir->i_sb, err);
2091cleanup:
2092 brelse(bh);
2093 dx_release(frames);
2094 return err;
2095}
2096
2097/*
2098 * ext4_generic_delete_entry deletes a directory entry by merging it
2099 * with the previous entry
2100 */
2101int ext4_generic_delete_entry(handle_t *handle,
2102 struct inode *dir,
2103 struct ext4_dir_entry_2 *de_del,
2104 struct buffer_head *bh,
2105 void *entry_buf,
2106 int buf_size,
2107 int csum_size)
2108{
2109 struct ext4_dir_entry_2 *de, *pde;
2110 unsigned int blocksize = dir->i_sb->s_blocksize;
2111 int i;
2112
2113 i = 0;
2114 pde = NULL;
2115 de = (struct ext4_dir_entry_2 *)entry_buf;
2116 while (i < buf_size - csum_size) {
2117 if (ext4_check_dir_entry(dir, NULL, de, bh,
2118 bh->b_data, bh->b_size, i))
2119 return -EIO;
2120 if (de == de_del) {
2121 if (pde)
2122 pde->rec_len = ext4_rec_len_to_disk(
2123 ext4_rec_len_from_disk(pde->rec_len,
2124 blocksize) +
2125 ext4_rec_len_from_disk(de->rec_len,
2126 blocksize),
2127 blocksize);
2128 else
2129 de->inode = 0;
2130 dir->i_version++;
2131 return 0;
2132 }
2133 i += ext4_rec_len_from_disk(de->rec_len, blocksize);
2134 pde = de;
2135 de = ext4_next_entry(de, blocksize);
2136 }
2137 return -ENOENT;
2138}
2139
2140static int ext4_delete_entry(handle_t *handle,
2141 struct inode *dir,
2142 struct ext4_dir_entry_2 *de_del,
2143 struct buffer_head *bh)
2144{
2145 int err, csum_size = 0;
2146
2147 if (ext4_has_inline_data(dir)) {
2148 int has_inline_data = 1;
2149 err = ext4_delete_inline_entry(handle, dir, de_del, bh,
2150 &has_inline_data);
2151 if (has_inline_data)
2152 return err;
2153 }
2154
2155 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2156 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2157 csum_size = sizeof(struct ext4_dir_entry_tail);
2158
2159 BUFFER_TRACE(bh, "get_write_access");
2160 err = ext4_journal_get_write_access(handle, bh);
2161 if (unlikely(err))
2162 goto out;
2163
2164 err = ext4_generic_delete_entry(handle, dir, de_del,
2165 bh, bh->b_data,
2166 dir->i_sb->s_blocksize, csum_size);
2167 if (err)
2168 goto out;
2169
2170 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2171 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
2172 if (unlikely(err))
2173 goto out;
2174
2175 return 0;
2176out:
2177 if (err != -ENOENT)
2178 ext4_std_error(dir->i_sb, err);
2179 return err;
2180}
2181
2182/*
2183 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2,
2184 * since this indicates that nlinks count was previously 1.
2185 */
2186static void ext4_inc_count(handle_t *handle, struct inode *inode)
2187{
2188 inc_nlink(inode);
2189 if (is_dx(inode) && inode->i_nlink > 1) {
2190 /* limit is 16-bit i_links_count */
2191 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) {
2192 set_nlink(inode, 1);
2193 EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb,
2194 EXT4_FEATURE_RO_COMPAT_DIR_NLINK);
2195 }
2196 }
2197}
2198
2199/*
2200 * If a directory had nlink == 1, then we should let it be 1. This indicates
2201 * directory has >EXT4_LINK_MAX subdirs.
2202 */
2203static void ext4_dec_count(handle_t *handle, struct inode *inode)
2204{
2205 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2206 drop_nlink(inode);
2207}
2208
2209
2210static int ext4_add_nondir(handle_t *handle,
2211 struct dentry *dentry, struct inode *inode)
2212{
2213 int err = ext4_add_entry(handle, dentry, inode);
2214 if (!err) {
2215 ext4_mark_inode_dirty(handle, inode);
2216 unlock_new_inode(inode);
2217 d_instantiate(dentry, inode);
2218 return 0;
2219 }
2220 drop_nlink(inode);
2221 unlock_new_inode(inode);
2222 iput(inode);
2223 return err;
2224}
2225
2226/*
2227 * By the time this is called, we already have created
2228 * the directory cache entry for the new file, but it
2229 * is so far negative - it has no inode.
2230 *
2231 * If the create succeeds, we fill in the inode information
2232 * with d_instantiate().
2233 */
2234static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
2235 bool excl)
2236{
2237 handle_t *handle;
2238 struct inode *inode;
2239 int err, credits, retries = 0;
2240
2241 dquot_initialize(dir);
2242
2243 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2244 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2245retry:
2246 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2247 NULL, EXT4_HT_DIR, credits);
2248 handle = ext4_journal_current_handle();
2249 err = PTR_ERR(inode);
2250 if (!IS_ERR(inode)) {
2251 inode->i_op = &ext4_file_inode_operations;
2252 inode->i_fop = &ext4_file_operations;
2253 ext4_set_aops(inode);
2254 err = ext4_add_nondir(handle, dentry, inode);
2255 if (!err && IS_DIRSYNC(dir))
2256 ext4_handle_sync(handle);
2257 }
2258 if (handle)
2259 ext4_journal_stop(handle);
2260 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2261 goto retry;
2262 return err;
2263}
2264
2265static int ext4_mknod(struct inode *dir, struct dentry *dentry,
2266 umode_t mode, dev_t rdev)
2267{
2268 handle_t *handle;
2269 struct inode *inode;
2270 int err, credits, retries = 0;
2271
2272 if (!new_valid_dev(rdev))
2273 return -EINVAL;
2274
2275 dquot_initialize(dir);
2276
2277 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2278 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2279retry:
2280 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2281 NULL, EXT4_HT_DIR, credits);
2282 handle = ext4_journal_current_handle();
2283 err = PTR_ERR(inode);
2284 if (!IS_ERR(inode)) {
2285 init_special_inode(inode, inode->i_mode, rdev);
2286 inode->i_op = &ext4_special_inode_operations;
2287 err = ext4_add_nondir(handle, dentry, inode);
2288 if (!err && IS_DIRSYNC(dir))
2289 ext4_handle_sync(handle);
2290 }
2291 if (handle)
2292 ext4_journal_stop(handle);
2293 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2294 goto retry;
2295 return err;
2296}
2297
2298static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
2299{
2300 handle_t *handle;
2301 struct inode *inode;
2302 int err, retries = 0;
2303
2304 dquot_initialize(dir);
2305
2306retry:
2307 inode = ext4_new_inode_start_handle(dir, mode,
2308 NULL, 0, NULL,
2309 EXT4_HT_DIR,
2310 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2311 4 + EXT4_XATTR_TRANS_BLOCKS);
2312 handle = ext4_journal_current_handle();
2313 err = PTR_ERR(inode);
2314 if (!IS_ERR(inode)) {
2315 inode->i_op = &ext4_file_inode_operations;
2316 inode->i_fop = &ext4_file_operations;
2317 ext4_set_aops(inode);
2318 d_tmpfile(dentry, inode);
2319 err = ext4_orphan_add(handle, inode);
2320 if (err)
2321 goto err_unlock_inode;
2322 mark_inode_dirty(inode);
2323 unlock_new_inode(inode);
2324 }
2325 if (handle)
2326 ext4_journal_stop(handle);
2327 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2328 goto retry;
2329 return err;
2330err_unlock_inode:
2331 ext4_journal_stop(handle);
2332 unlock_new_inode(inode);
2333 return err;
2334}
2335
2336struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2337 struct ext4_dir_entry_2 *de,
2338 int blocksize, int csum_size,
2339 unsigned int parent_ino, int dotdot_real_len)
2340{
2341 de->inode = cpu_to_le32(inode->i_ino);
2342 de->name_len = 1;
2343 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2344 blocksize);
2345 strcpy(de->name, ".");
2346 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2347
2348 de = ext4_next_entry(de, blocksize);
2349 de->inode = cpu_to_le32(parent_ino);
2350 de->name_len = 2;
2351 if (!dotdot_real_len)
2352 de->rec_len = ext4_rec_len_to_disk(blocksize -
2353 (csum_size + EXT4_DIR_REC_LEN(1)),
2354 blocksize);
2355 else
2356 de->rec_len = ext4_rec_len_to_disk(
2357 EXT4_DIR_REC_LEN(de->name_len), blocksize);
2358 strcpy(de->name, "..");
2359 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2360
2361 return ext4_next_entry(de, blocksize);
2362}
2363
2364static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2365 struct inode *inode)
2366{
2367 struct buffer_head *dir_block = NULL;
2368 struct ext4_dir_entry_2 *de;
2369 struct ext4_dir_entry_tail *t;
2370 ext4_lblk_t block = 0;
2371 unsigned int blocksize = dir->i_sb->s_blocksize;
2372 int csum_size = 0;
2373 int err;
2374
2375 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2376 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2377 csum_size = sizeof(struct ext4_dir_entry_tail);
2378
2379 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
2380 err = ext4_try_create_inline_dir(handle, dir, inode);
2381 if (err < 0 && err != -ENOSPC)
2382 goto out;
2383 if (!err)
2384 goto out;
2385 }
2386
2387 inode->i_size = 0;
2388 dir_block = ext4_append(handle, inode, &block);
2389 if (IS_ERR(dir_block))
2390 return PTR_ERR(dir_block);
2391 BUFFER_TRACE(dir_block, "get_write_access");
2392 err = ext4_journal_get_write_access(handle, dir_block);
2393 if (err)
2394 goto out;
2395 de = (struct ext4_dir_entry_2 *)dir_block->b_data;
2396 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
2397 set_nlink(inode, 2);
2398 if (csum_size) {
2399 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
2400 initialize_dirent_tail(t, blocksize);
2401 }
2402
2403 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2404 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
2405 if (err)
2406 goto out;
2407 set_buffer_verified(dir_block);
2408out:
2409 brelse(dir_block);
2410 return err;
2411}
2412
2413static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2414{
2415 handle_t *handle;
2416 struct inode *inode;
2417 int err, credits, retries = 0;
2418
2419 if (EXT4_DIR_LINK_MAX(dir))
2420 return -EMLINK;
2421
2422 dquot_initialize(dir);
2423
2424 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2425 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2426retry:
2427 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
2428 &dentry->d_name,
2429 0, NULL, EXT4_HT_DIR, credits);
2430 handle = ext4_journal_current_handle();
2431 err = PTR_ERR(inode);
2432 if (IS_ERR(inode))
2433 goto out_stop;
2434
2435 inode->i_op = &ext4_dir_inode_operations;
2436 inode->i_fop = &ext4_dir_operations;
2437 err = ext4_init_new_dir(handle, dir, inode);
2438 if (err)
2439 goto out_clear_inode;
2440 err = ext4_mark_inode_dirty(handle, inode);
2441 if (!err)
2442 err = ext4_add_entry(handle, dentry, inode);
2443 if (err) {
2444out_clear_inode:
2445 clear_nlink(inode);
2446 unlock_new_inode(inode);
2447 ext4_mark_inode_dirty(handle, inode);
2448 iput(inode);
2449 goto out_stop;
2450 }
2451 ext4_inc_count(handle, dir);
2452 ext4_update_dx_flag(dir);
2453 err = ext4_mark_inode_dirty(handle, dir);
2454 if (err)
2455 goto out_clear_inode;
2456 unlock_new_inode(inode);
2457 d_instantiate(dentry, inode);
2458 if (IS_DIRSYNC(dir))
2459 ext4_handle_sync(handle);
2460
2461out_stop:
2462 if (handle)
2463 ext4_journal_stop(handle);
2464 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2465 goto retry;
2466 return err;
2467}
2468
2469/*
2470 * routine to check that the specified directory is empty (for rmdir)
2471 */
2472static int empty_dir(struct inode *inode)
2473{
2474 unsigned int offset;
2475 struct buffer_head *bh;
2476 struct ext4_dir_entry_2 *de, *de1;
2477 struct super_block *sb;
2478 int err = 0;
2479
2480 if (ext4_has_inline_data(inode)) {
2481 int has_inline_data = 1;
2482
2483 err = empty_inline_dir(inode, &has_inline_data);
2484 if (has_inline_data)
2485 return err;
2486 }
2487
2488 sb = inode->i_sb;
2489 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
2490 EXT4_ERROR_INODE(inode, "invalid size");
2491 return 1;
2492 }
2493 bh = ext4_read_dirblock(inode, 0, EITHER);
2494 if (IS_ERR(bh))
2495 return 1;
2496
2497 de = (struct ext4_dir_entry_2 *) bh->b_data;
2498 de1 = ext4_next_entry(de, sb->s_blocksize);
2499 if (le32_to_cpu(de->inode) != inode->i_ino ||
2500 !le32_to_cpu(de1->inode) ||
2501 strcmp(".", de->name) ||
2502 strcmp("..", de1->name)) {
2503 ext4_warning(inode->i_sb,
2504 "bad directory (dir #%lu) - no `.' or `..'",
2505 inode->i_ino);
2506 brelse(bh);
2507 return 1;
2508 }
2509 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
2510 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
2511 de = ext4_next_entry(de1, sb->s_blocksize);
2512 while (offset < inode->i_size) {
2513 if (!bh ||
2514 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
2515 unsigned int lblock;
2516 err = 0;
2517 brelse(bh);
2518 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
2519 bh = ext4_read_dirblock(inode, lblock, EITHER);
2520 if (IS_ERR(bh))
2521 return 1;
2522 de = (struct ext4_dir_entry_2 *) bh->b_data;
2523 }
2524 if (ext4_check_dir_entry(inode, NULL, de, bh,
2525 bh->b_data, bh->b_size, offset)) {
2526 de = (struct ext4_dir_entry_2 *)(bh->b_data +
2527 sb->s_blocksize);
2528 offset = (offset | (sb->s_blocksize - 1)) + 1;
2529 continue;
2530 }
2531 if (le32_to_cpu(de->inode)) {
2532 brelse(bh);
2533 return 0;
2534 }
2535 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2536 de = ext4_next_entry(de, sb->s_blocksize);
2537 }
2538 brelse(bh);
2539 return 1;
2540}
2541
2542/* ext4_orphan_add() links an unlinked or truncated inode into a list of
2543 * such inodes, starting at the superblock, in case we crash before the
2544 * file is closed/deleted, or in case the inode truncate spans multiple
2545 * transactions and the last transaction is not recovered after a crash.
2546 *
2547 * At filesystem recovery time, we walk this list deleting unlinked
2548 * inodes and truncating linked inodes in ext4_orphan_cleanup().
2549 */
2550int ext4_orphan_add(handle_t *handle, struct inode *inode)
2551{
2552 struct super_block *sb = inode->i_sb;
2553 struct ext4_iloc iloc;
2554 int err = 0, rc;
2555
2556 if (!EXT4_SB(sb)->s_journal)
2557 return 0;
2558
2559 mutex_lock(&EXT4_SB(sb)->s_orphan_lock);
2560 if (!list_empty(&EXT4_I(inode)->i_orphan))
2561 goto out_unlock;
2562
2563 /*
2564 * Orphan handling is only valid for files with data blocks
2565 * being truncated, or files being unlinked. Note that we either
2566 * hold i_mutex, or the inode can not be referenced from outside,
2567 * so i_nlink should not be bumped due to race
2568 */
2569 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2570 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
2571
2572 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
2573 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
2574 if (err)
2575 goto out_unlock;
2576
2577 err = ext4_reserve_inode_write(handle, inode, &iloc);
2578 if (err)
2579 goto out_unlock;
2580 /*
2581 * Due to previous errors inode may be already a part of on-disk
2582 * orphan list. If so skip on-disk list modification.
2583 */
2584 if (NEXT_ORPHAN(inode) && NEXT_ORPHAN(inode) <=
2585 (le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)))
2586 goto mem_insert;
2587
2588 /* Insert this inode at the head of the on-disk orphan list... */
2589 NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan);
2590 EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2591 err = ext4_handle_dirty_super(handle, sb);
2592 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
2593 if (!err)
2594 err = rc;
2595
2596 /* Only add to the head of the in-memory list if all the
2597 * previous operations succeeded. If the orphan_add is going to
2598 * fail (possibly taking the journal offline), we can't risk
2599 * leaving the inode on the orphan list: stray orphan-list
2600 * entries can cause panics at unmount time.
2601 *
2602 * This is safe: on error we're going to ignore the orphan list
2603 * anyway on the next recovery. */
2604mem_insert:
2605 if (!err)
2606 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2607
2608 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
2609 jbd_debug(4, "orphan inode %lu will point to %d\n",
2610 inode->i_ino, NEXT_ORPHAN(inode));
2611out_unlock:
2612 mutex_unlock(&EXT4_SB(sb)->s_orphan_lock);
2613 ext4_std_error(inode->i_sb, err);
2614 return err;
2615}
2616
2617/*
2618 * ext4_orphan_del() removes an unlinked or truncated inode from the list
2619 * of such inodes stored on disk, because it is finally being cleaned up.
2620 */
2621int ext4_orphan_del(handle_t *handle, struct inode *inode)
2622{
2623 struct list_head *prev;
2624 struct ext4_inode_info *ei = EXT4_I(inode);
2625 struct ext4_sb_info *sbi;
2626 __u32 ino_next;
2627 struct ext4_iloc iloc;
2628 int err = 0;
2629
2630 if ((!EXT4_SB(inode->i_sb)->s_journal) &&
2631 !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS))
2632 return 0;
2633
2634 mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
2635 if (list_empty(&ei->i_orphan))
2636 goto out;
2637
2638 ino_next = NEXT_ORPHAN(inode);
2639 prev = ei->i_orphan.prev;
2640 sbi = EXT4_SB(inode->i_sb);
2641
2642 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
2643
2644 list_del_init(&ei->i_orphan);
2645
2646 /* If we're on an error path, we may not have a valid
2647 * transaction handle with which to update the orphan list on
2648 * disk, but we still need to remove the inode from the linked
2649 * list in memory. */
2650 if (!handle)
2651 goto out;
2652
2653 err = ext4_reserve_inode_write(handle, inode, &iloc);
2654 if (err)
2655 goto out_err;
2656
2657 if (prev == &sbi->s_orphan) {
2658 jbd_debug(4, "superblock will point to %u\n", ino_next);
2659 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2660 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
2661 if (err)
2662 goto out_brelse;
2663 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
2664 err = ext4_handle_dirty_super(handle, inode->i_sb);
2665 } else {
2666 struct ext4_iloc iloc2;
2667 struct inode *i_prev =
2668 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
2669
2670 jbd_debug(4, "orphan inode %lu will point to %u\n",
2671 i_prev->i_ino, ino_next);
2672 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
2673 if (err)
2674 goto out_brelse;
2675 NEXT_ORPHAN(i_prev) = ino_next;
2676 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
2677 }
2678 if (err)
2679 goto out_brelse;
2680 NEXT_ORPHAN(inode) = 0;
2681 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
2682
2683out_err:
2684 ext4_std_error(inode->i_sb, err);
2685out:
2686 mutex_unlock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
2687 return err;
2688
2689out_brelse:
2690 brelse(iloc.bh);
2691 goto out_err;
2692}
2693
2694static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
2695{
2696 int retval;
2697 struct inode *inode;
2698 struct buffer_head *bh;
2699 struct ext4_dir_entry_2 *de;
2700 handle_t *handle = NULL;
2701
2702 /* Initialize quotas before so that eventual writes go in
2703 * separate transaction */
2704 dquot_initialize(dir);
2705 dquot_initialize(dentry->d_inode);
2706
2707 retval = -ENOENT;
2708 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
2709 if (!bh)
2710 goto end_rmdir;
2711
2712 inode = dentry->d_inode;
2713
2714 retval = -EIO;
2715 if (le32_to_cpu(de->inode) != inode->i_ino)
2716 goto end_rmdir;
2717
2718 retval = -ENOTEMPTY;
2719 if (!empty_dir(inode))
2720 goto end_rmdir;
2721
2722 handle = ext4_journal_start(dir, EXT4_HT_DIR,
2723 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
2724 if (IS_ERR(handle)) {
2725 retval = PTR_ERR(handle);
2726 handle = NULL;
2727 goto end_rmdir;
2728 }
2729
2730 if (IS_DIRSYNC(dir))
2731 ext4_handle_sync(handle);
2732
2733 retval = ext4_delete_entry(handle, dir, de, bh);
2734 if (retval)
2735 goto end_rmdir;
2736 if (!EXT4_DIR_LINK_EMPTY(inode))
2737 ext4_warning(inode->i_sb,
2738 "empty directory has too many links (%d)",
2739 inode->i_nlink);
2740 inode->i_version++;
2741 clear_nlink(inode);
2742 /* There's no need to set i_disksize: the fact that i_nlink is
2743 * zero will ensure that the right thing happens during any
2744 * recovery. */
2745 inode->i_size = 0;
2746 ext4_orphan_add(handle, inode);
2747 inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode);
2748 ext4_mark_inode_dirty(handle, inode);
2749 ext4_dec_count(handle, dir);
2750 ext4_update_dx_flag(dir);
2751 ext4_mark_inode_dirty(handle, dir);
2752
2753end_rmdir:
2754 brelse(bh);
2755 if (handle)
2756 ext4_journal_stop(handle);
2757 return retval;
2758}
2759
2760static int ext4_unlink(struct inode *dir, struct dentry *dentry)
2761{
2762 int retval;
2763 struct inode *inode;
2764 struct buffer_head *bh;
2765 struct ext4_dir_entry_2 *de;
2766 handle_t *handle = NULL;
2767
2768 trace_ext4_unlink_enter(dir, dentry);
2769 /* Initialize quotas before so that eventual writes go
2770 * in separate transaction */
2771 dquot_initialize(dir);
2772 dquot_initialize(dentry->d_inode);
2773
2774 retval = -ENOENT;
2775 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
2776 if (!bh)
2777 goto end_unlink;
2778
2779 inode = dentry->d_inode;
2780
2781 retval = -EIO;
2782 if (le32_to_cpu(de->inode) != inode->i_ino)
2783 goto end_unlink;
2784
2785 handle = ext4_journal_start(dir, EXT4_HT_DIR,
2786 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
2787 if (IS_ERR(handle)) {
2788 retval = PTR_ERR(handle);
2789 handle = NULL;
2790 goto end_unlink;
2791 }
2792
2793 if (IS_DIRSYNC(dir))
2794 ext4_handle_sync(handle);
2795
2796 if (!inode->i_nlink) {
2797 ext4_warning(inode->i_sb,
2798 "Deleting nonexistent file (%lu), %d",
2799 inode->i_ino, inode->i_nlink);
2800 set_nlink(inode, 1);
2801 }
2802 retval = ext4_delete_entry(handle, dir, de, bh);
2803 if (retval)
2804 goto end_unlink;
2805 dir->i_ctime = dir->i_mtime = ext4_current_time(dir);
2806 ext4_update_dx_flag(dir);
2807 ext4_mark_inode_dirty(handle, dir);
2808 drop_nlink(inode);
2809 if (!inode->i_nlink)
2810 ext4_orphan_add(handle, inode);
2811 inode->i_ctime = ext4_current_time(inode);
2812 ext4_mark_inode_dirty(handle, inode);
2813 retval = 0;
2814
2815end_unlink:
2816 brelse(bh);
2817 if (handle)
2818 ext4_journal_stop(handle);
2819 trace_ext4_unlink_exit(dentry, retval);
2820 return retval;
2821}
2822
2823static int ext4_symlink(struct inode *dir,
2824 struct dentry *dentry, const char *symname)
2825{
2826 handle_t *handle;
2827 struct inode *inode;
2828 int l, err, retries = 0;
2829 int credits;
2830
2831 l = strlen(symname)+1;
2832 if (l > dir->i_sb->s_blocksize)
2833 return -ENAMETOOLONG;
2834
2835 dquot_initialize(dir);
2836
2837 if (l > EXT4_N_BLOCKS * 4) {
2838 /*
2839 * For non-fast symlinks, we just allocate inode and put it on
2840 * orphan list in the first transaction => we need bitmap,
2841 * group descriptor, sb, inode block, quota blocks, and
2842 * possibly selinux xattr blocks.
2843 */
2844 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2845 EXT4_XATTR_TRANS_BLOCKS;
2846 } else {
2847 /*
2848 * Fast symlink. We have to add entry to directory
2849 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
2850 * allocate new inode (bitmap, group descriptor, inode block,
2851 * quota blocks, sb is already counted in previous macros).
2852 */
2853 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2854 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
2855 }
2856retry:
2857 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
2858 &dentry->d_name, 0, NULL,
2859 EXT4_HT_DIR, credits);
2860 handle = ext4_journal_current_handle();
2861 err = PTR_ERR(inode);
2862 if (IS_ERR(inode))
2863 goto out_stop;
2864
2865 if (l > EXT4_N_BLOCKS * 4) {
2866 inode->i_op = &ext4_symlink_inode_operations;
2867 ext4_set_aops(inode);
2868 /*
2869 * We cannot call page_symlink() with transaction started
2870 * because it calls into ext4_write_begin() which can wait
2871 * for transaction commit if we are running out of space
2872 * and thus we deadlock. So we have to stop transaction now
2873 * and restart it when symlink contents is written.
2874 *
2875 * To keep fs consistent in case of crash, we have to put inode
2876 * to orphan list in the mean time.
2877 */
2878 drop_nlink(inode);
2879 err = ext4_orphan_add(handle, inode);
2880 ext4_journal_stop(handle);
2881 if (err)
2882 goto err_drop_inode;
2883 err = __page_symlink(inode, symname, l, 1);
2884 if (err)
2885 goto err_drop_inode;
2886 /*
2887 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
2888 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
2889 */
2890 handle = ext4_journal_start(dir, EXT4_HT_DIR,
2891 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2892 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
2893 if (IS_ERR(handle)) {
2894 err = PTR_ERR(handle);
2895 goto err_drop_inode;
2896 }
2897 set_nlink(inode, 1);
2898 err = ext4_orphan_del(handle, inode);
2899 if (err) {
2900 ext4_journal_stop(handle);
2901 clear_nlink(inode);
2902 goto err_drop_inode;
2903 }
2904 } else {
2905 /* clear the extent format for fast symlink */
2906 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
2907 inode->i_op = &ext4_fast_symlink_inode_operations;
2908 memcpy((char *)&EXT4_I(inode)->i_data, symname, l);
2909 inode->i_size = l-1;
2910 }
2911 EXT4_I(inode)->i_disksize = inode->i_size;
2912 err = ext4_add_nondir(handle, dentry, inode);
2913 if (!err && IS_DIRSYNC(dir))
2914 ext4_handle_sync(handle);
2915
2916out_stop:
2917 if (handle)
2918 ext4_journal_stop(handle);
2919 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2920 goto retry;
2921 return err;
2922err_drop_inode:
2923 unlock_new_inode(inode);
2924 iput(inode);
2925 return err;
2926}
2927
2928static int ext4_link(struct dentry *old_dentry,
2929 struct inode *dir, struct dentry *dentry)
2930{
2931 handle_t *handle;
2932 struct inode *inode = old_dentry->d_inode;
2933 int err, retries = 0;
2934
2935 if (inode->i_nlink >= EXT4_LINK_MAX)
2936 return -EMLINK;
2937
2938 dquot_initialize(dir);
2939
2940retry:
2941 handle = ext4_journal_start(dir, EXT4_HT_DIR,
2942 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2943 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
2944 if (IS_ERR(handle))
2945 return PTR_ERR(handle);
2946
2947 if (IS_DIRSYNC(dir))
2948 ext4_handle_sync(handle);
2949
2950 inode->i_ctime = ext4_current_time(inode);
2951 ext4_inc_count(handle, inode);
2952 ihold(inode);
2953
2954 err = ext4_add_entry(handle, dentry, inode);
2955 if (!err) {
2956 ext4_mark_inode_dirty(handle, inode);
2957 /* this can happen only for tmpfile being
2958 * linked the first time
2959 */
2960 if (inode->i_nlink == 1)
2961 ext4_orphan_del(handle, inode);
2962 d_instantiate(dentry, inode);
2963 } else {
2964 drop_nlink(inode);
2965 iput(inode);
2966 }
2967 ext4_journal_stop(handle);
2968 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2969 goto retry;
2970 return err;
2971}
2972
2973
2974/*
2975 * Try to find buffer head where contains the parent block.
2976 * It should be the inode block if it is inlined or the 1st block
2977 * if it is a normal dir.
2978 */
2979static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
2980 struct inode *inode,
2981 int *retval,
2982 struct ext4_dir_entry_2 **parent_de,
2983 int *inlined)
2984{
2985 struct buffer_head *bh;
2986
2987 if (!ext4_has_inline_data(inode)) {
2988 bh = ext4_read_dirblock(inode, 0, EITHER);
2989 if (IS_ERR(bh)) {
2990 *retval = PTR_ERR(bh);
2991 return NULL;
2992 }
2993 *parent_de = ext4_next_entry(
2994 (struct ext4_dir_entry_2 *)bh->b_data,
2995 inode->i_sb->s_blocksize);
2996 return bh;
2997 }
2998
2999 *inlined = 1;
3000 return ext4_get_first_inline_block(inode, parent_de, retval);
3001}
3002
3003struct ext4_renament {
3004 struct inode *dir;
3005 struct dentry *dentry;
3006 struct inode *inode;
3007 bool is_dir;
3008 int dir_nlink_delta;
3009
3010 /* entry for "dentry" */
3011 struct buffer_head *bh;
3012 struct ext4_dir_entry_2 *de;
3013 int inlined;
3014
3015 /* entry for ".." in inode if it's a directory */
3016 struct buffer_head *dir_bh;
3017 struct ext4_dir_entry_2 *parent_de;
3018 int dir_inlined;
3019};
3020
3021static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
3022{
3023 int retval;
3024
3025 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
3026 &retval, &ent->parent_de,
3027 &ent->dir_inlined);
3028 if (!ent->dir_bh)
3029 return retval;
3030 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
3031 return -EIO;
3032 BUFFER_TRACE(ent->dir_bh, "get_write_access");
3033 return ext4_journal_get_write_access(handle, ent->dir_bh);
3034}
3035
3036static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
3037 unsigned dir_ino)
3038{
3039 int retval;
3040
3041 ent->parent_de->inode = cpu_to_le32(dir_ino);
3042 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
3043 if (!ent->dir_inlined) {
3044 if (is_dx(ent->inode)) {
3045 retval = ext4_handle_dirty_dx_node(handle,
3046 ent->inode,
3047 ent->dir_bh);
3048 } else {
3049 retval = ext4_handle_dirty_dirent_node(handle,
3050 ent->inode,
3051 ent->dir_bh);
3052 }
3053 } else {
3054 retval = ext4_mark_inode_dirty(handle, ent->inode);
3055 }
3056 if (retval) {
3057 ext4_std_error(ent->dir->i_sb, retval);
3058 return retval;
3059 }
3060 return 0;
3061}
3062
3063static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
3064 unsigned ino, unsigned file_type)
3065{
3066 int retval;
3067
3068 BUFFER_TRACE(ent->bh, "get write access");
3069 retval = ext4_journal_get_write_access(handle, ent->bh);
3070 if (retval)
3071 return retval;
3072 ent->de->inode = cpu_to_le32(ino);
3073 if (EXT4_HAS_INCOMPAT_FEATURE(ent->dir->i_sb,
3074 EXT4_FEATURE_INCOMPAT_FILETYPE))
3075 ent->de->file_type = file_type;
3076 ent->dir->i_version++;
3077 ent->dir->i_ctime = ent->dir->i_mtime =
3078 ext4_current_time(ent->dir);
3079 ext4_mark_inode_dirty(handle, ent->dir);
3080 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
3081 if (!ent->inlined) {
3082 retval = ext4_handle_dirty_dirent_node(handle,
3083 ent->dir, ent->bh);
3084 if (unlikely(retval)) {
3085 ext4_std_error(ent->dir->i_sb, retval);
3086 return retval;
3087 }
3088 }
3089 brelse(ent->bh);
3090 ent->bh = NULL;
3091
3092 return 0;
3093}
3094
3095static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
3096 const struct qstr *d_name)
3097{
3098 int retval = -ENOENT;
3099 struct buffer_head *bh;
3100 struct ext4_dir_entry_2 *de;
3101
3102 bh = ext4_find_entry(dir, d_name, &de, NULL);
3103 if (bh) {
3104 retval = ext4_delete_entry(handle, dir, de, bh);
3105 brelse(bh);
3106 }
3107 return retval;
3108}
3109
3110static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent)
3111{
3112 int retval;
3113 /*
3114 * ent->de could have moved from under us during htree split, so make
3115 * sure that we are deleting the right entry. We might also be pointing
3116 * to a stale entry in the unused part of ent->bh so just checking inum
3117 * and the name isn't enough.
3118 */
3119 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
3120 ent->de->name_len != ent->dentry->d_name.len ||
3121 strncmp(ent->de->name, ent->dentry->d_name.name,
3122 ent->de->name_len)) {
3123 retval = ext4_find_delete_entry(handle, ent->dir,
3124 &ent->dentry->d_name);
3125 } else {
3126 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
3127 if (retval == -ENOENT) {
3128 retval = ext4_find_delete_entry(handle, ent->dir,
3129 &ent->dentry->d_name);
3130 }
3131 }
3132
3133 if (retval) {
3134 ext4_warning(ent->dir->i_sb,
3135 "Deleting old file (%lu), %d, error=%d",
3136 ent->dir->i_ino, ent->dir->i_nlink, retval);
3137 }
3138}
3139
3140static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
3141{
3142 if (ent->dir_nlink_delta) {
3143 if (ent->dir_nlink_delta == -1)
3144 ext4_dec_count(handle, ent->dir);
3145 else
3146 ext4_inc_count(handle, ent->dir);
3147 ext4_mark_inode_dirty(handle, ent->dir);
3148 }
3149}
3150
3151/*
3152 * Anybody can rename anything with this: the permission checks are left to the
3153 * higher-level routines.
3154 *
3155 * n.b. old_{dentry,inode) refers to the source dentry/inode
3156 * while new_{dentry,inode) refers to the destination dentry/inode
3157 * This comes from rename(const char *oldpath, const char *newpath)
3158 */
3159static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
3160 struct inode *new_dir, struct dentry *new_dentry)
3161{
3162 handle_t *handle = NULL;
3163 struct ext4_renament old = {
3164 .dir = old_dir,
3165 .dentry = old_dentry,
3166 .inode = old_dentry->d_inode,
3167 };
3168 struct ext4_renament new = {
3169 .dir = new_dir,
3170 .dentry = new_dentry,
3171 .inode = new_dentry->d_inode,
3172 };
3173 int retval;
3174
3175 dquot_initialize(old.dir);
3176 dquot_initialize(new.dir);
3177
3178 /* Initialize quotas before so that eventual writes go
3179 * in separate transaction */
3180 if (new.inode)
3181 dquot_initialize(new.inode);
3182
3183 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
3184 /*
3185 * Check for inode number is _not_ due to possible IO errors.
3186 * We might rmdir the source, keep it as pwd of some process
3187 * and merrily kill the link to whatever was created under the
3188 * same name. Goodbye sticky bit ;-<
3189 */
3190 retval = -ENOENT;
3191 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3192 goto end_rename;
3193
3194 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3195 &new.de, &new.inlined);
3196 if (new.bh) {
3197 if (!new.inode) {
3198 brelse(new.bh);
3199 new.bh = NULL;
3200 }
3201 }
3202 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
3203 ext4_alloc_da_blocks(old.inode);
3204
3205 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
3206 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3207 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
3208 if (IS_ERR(handle))
3209 return PTR_ERR(handle);
3210
3211 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3212 ext4_handle_sync(handle);
3213
3214 if (S_ISDIR(old.inode->i_mode)) {
3215 if (new.inode) {
3216 retval = -ENOTEMPTY;
3217 if (!empty_dir(new.inode))
3218 goto end_rename;
3219 } else {
3220 retval = -EMLINK;
3221 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
3222 goto end_rename;
3223 }
3224 retval = ext4_rename_dir_prepare(handle, &old);
3225 if (retval)
3226 goto end_rename;
3227 }
3228 if (!new.bh) {
3229 retval = ext4_add_entry(handle, new.dentry, old.inode);
3230 if (retval)
3231 goto end_rename;
3232 } else {
3233 retval = ext4_setent(handle, &new,
3234 old.inode->i_ino, old.de->file_type);
3235 if (retval)
3236 goto end_rename;
3237 }
3238
3239 /*
3240 * Like most other Unix systems, set the ctime for inodes on a
3241 * rename.
3242 */
3243 old.inode->i_ctime = ext4_current_time(old.inode);
3244 ext4_mark_inode_dirty(handle, old.inode);
3245
3246 /*
3247 * ok, that's it
3248 */
3249 ext4_rename_delete(handle, &old);
3250
3251 if (new.inode) {
3252 ext4_dec_count(handle, new.inode);
3253 new.inode->i_ctime = ext4_current_time(new.inode);
3254 }
3255 old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir);
3256 ext4_update_dx_flag(old.dir);
3257 if (old.dir_bh) {
3258 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3259 if (retval)
3260 goto end_rename;
3261
3262 ext4_dec_count(handle, old.dir);
3263 if (new.inode) {
3264 /* checked empty_dir above, can't have another parent,
3265 * ext4_dec_count() won't work for many-linked dirs */
3266 clear_nlink(new.inode);
3267 } else {
3268 ext4_inc_count(handle, new.dir);
3269 ext4_update_dx_flag(new.dir);
3270 ext4_mark_inode_dirty(handle, new.dir);
3271 }
3272 }
3273 ext4_mark_inode_dirty(handle, old.dir);
3274 if (new.inode) {
3275 ext4_mark_inode_dirty(handle, new.inode);
3276 if (!new.inode->i_nlink)
3277 ext4_orphan_add(handle, new.inode);
3278 }
3279 retval = 0;
3280
3281end_rename:
3282 brelse(old.dir_bh);
3283 brelse(old.bh);
3284 brelse(new.bh);
3285 if (handle)
3286 ext4_journal_stop(handle);
3287 return retval;
3288}
3289
3290static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
3291 struct inode *new_dir, struct dentry *new_dentry)
3292{
3293 handle_t *handle = NULL;
3294 struct ext4_renament old = {
3295 .dir = old_dir,
3296 .dentry = old_dentry,
3297 .inode = old_dentry->d_inode,
3298 };
3299 struct ext4_renament new = {
3300 .dir = new_dir,
3301 .dentry = new_dentry,
3302 .inode = new_dentry->d_inode,
3303 };
3304 u8 new_file_type;
3305 int retval;
3306
3307 dquot_initialize(old.dir);
3308 dquot_initialize(new.dir);
3309
3310 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
3311 &old.de, &old.inlined);
3312 /*
3313 * Check for inode number is _not_ due to possible IO errors.
3314 * We might rmdir the source, keep it as pwd of some process
3315 * and merrily kill the link to whatever was created under the
3316 * same name. Goodbye sticky bit ;-<
3317 */
3318 retval = -ENOENT;
3319 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3320 goto end_rename;
3321
3322 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3323 &new.de, &new.inlined);
3324
3325 /* RENAME_EXCHANGE case: old *and* new must both exist */
3326 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
3327 goto end_rename;
3328
3329 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
3330 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3331 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
3332 if (IS_ERR(handle))
3333 return PTR_ERR(handle);
3334
3335 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3336 ext4_handle_sync(handle);
3337
3338 if (S_ISDIR(old.inode->i_mode)) {
3339 old.is_dir = true;
3340 retval = ext4_rename_dir_prepare(handle, &old);
3341 if (retval)
3342 goto end_rename;
3343 }
3344 if (S_ISDIR(new.inode->i_mode)) {
3345 new.is_dir = true;
3346 retval = ext4_rename_dir_prepare(handle, &new);
3347 if (retval)
3348 goto end_rename;
3349 }
3350
3351 /*
3352 * Other than the special case of overwriting a directory, parents'
3353 * nlink only needs to be modified if this is a cross directory rename.
3354 */
3355 if (old.dir != new.dir && old.is_dir != new.is_dir) {
3356 old.dir_nlink_delta = old.is_dir ? -1 : 1;
3357 new.dir_nlink_delta = -old.dir_nlink_delta;
3358 retval = -EMLINK;
3359 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
3360 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
3361 goto end_rename;
3362 }
3363
3364 new_file_type = new.de->file_type;
3365 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
3366 if (retval)
3367 goto end_rename;
3368
3369 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
3370 if (retval)
3371 goto end_rename;
3372
3373 /*
3374 * Like most other Unix systems, set the ctime for inodes on a
3375 * rename.
3376 */
3377 old.inode->i_ctime = ext4_current_time(old.inode);
3378 new.inode->i_ctime = ext4_current_time(new.inode);
3379 ext4_mark_inode_dirty(handle, old.inode);
3380 ext4_mark_inode_dirty(handle, new.inode);
3381
3382 if (old.dir_bh) {
3383 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3384 if (retval)
3385 goto end_rename;
3386 }
3387 if (new.dir_bh) {
3388 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
3389 if (retval)
3390 goto end_rename;
3391 }
3392 ext4_update_dir_count(handle, &old);
3393 ext4_update_dir_count(handle, &new);
3394 retval = 0;
3395
3396end_rename:
3397 brelse(old.dir_bh);
3398 brelse(new.dir_bh);
3399 brelse(old.bh);
3400 brelse(new.bh);
3401 if (handle)
3402 ext4_journal_stop(handle);
3403 return retval;
3404}
3405
3406static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
3407 struct inode *new_dir, struct dentry *new_dentry,
3408 unsigned int flags)
3409{
3410 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
3411 return -EINVAL;
3412
3413 if (flags & RENAME_EXCHANGE) {
3414 return ext4_cross_rename(old_dir, old_dentry,
3415 new_dir, new_dentry);
3416 }
3417 /*
3418 * Existence checking was done by the VFS, otherwise "RENAME_NOREPLACE"
3419 * is equivalent to regular rename.
3420 */
3421 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry);
3422}
3423
3424/*
3425 * directories can handle most operations...
3426 */
3427const struct inode_operations ext4_dir_inode_operations = {
3428 .create = ext4_create,
3429 .lookup = ext4_lookup,
3430 .link = ext4_link,
3431 .unlink = ext4_unlink,
3432 .symlink = ext4_symlink,
3433 .mkdir = ext4_mkdir,
3434 .rmdir = ext4_rmdir,
3435 .mknod = ext4_mknod,
3436 .tmpfile = ext4_tmpfile,
3437 .rename = ext4_rename,
3438 .rename2 = ext4_rename2,
3439 .setattr = ext4_setattr,
3440 .setxattr = generic_setxattr,
3441 .getxattr = generic_getxattr,
3442 .listxattr = ext4_listxattr,
3443 .removexattr = generic_removexattr,
3444 .get_acl = ext4_get_acl,
3445 .set_acl = ext4_set_acl,
3446 .fiemap = ext4_fiemap,
3447};
3448
3449const struct inode_operations ext4_special_inode_operations = {
3450 .setattr = ext4_setattr,
3451 .setxattr = generic_setxattr,
3452 .getxattr = generic_getxattr,
3453 .listxattr = ext4_listxattr,
3454 .removexattr = generic_removexattr,
3455 .get_acl = ext4_get_acl,
3456 .set_acl = ext4_set_acl,
3457};