?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
i2c: tegra: Add Dmitry as a reviewer
[linux-2.6/linux-2.6-arm.git] / fs / ext4 / namei.c
blobcd01c4a67ffbd170567a1ab5ca07adb07a05aeb2
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/ext4/namei.c
4 *
5 * Copyright (C) 1992, 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Laboratoire MASI - Institut Blaise Pascal
8 * Universite Pierre et Marie Curie (Paris VI)
9 *
10 * from
11 *
12 * linux/fs/minix/namei.c
13 *
14 * Copyright (C) 1991, 1992 Linus Torvalds
15 *
16 * Big-endian to little-endian byte-swapping/bitmaps by
17 * David S. Miller (davem@caip.rutgers.edu), 1995
18 * Directory entry file type support and forward compatibility hooks
19 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
20 * Hash Tree Directory indexing (c)
21 * Daniel Phillips, 2001
22 * Hash Tree Directory indexing porting
23 * Christopher Li, 2002
24 * Hash Tree Directory indexing cleanup
25 * Theodore Ts'o, 2002
26 */
27
28 #include <linux/fs.h>
29 #include <linux/pagemap.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 <linux/iversion.h>
38 #include <linux/unicode.h>
39 #include "ext4.h"
40 #include "ext4_jbd2.h"
41
42 #include "xattr.h"
43 #include "acl.h"
44
45 #include <trace/events/ext4.h>
46 /*
47 * define how far ahead to read directories while searching them.
48 */
49 #define NAMEI_RA_CHUNKS 2
50 #define NAMEI_RA_BLOCKS 4
51 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
52
53 static struct buffer_head *ext4_append(handle_t *handle,
54 struct inode *inode,
55 ext4_lblk_t *block)
56 {
57 struct buffer_head *bh;
58 int err;
59
60 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
61 ((inode->i_size >> 10) >=
62 EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
63 return ERR_PTR(-ENOSPC);
64
65 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
66
67 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE);
68 if (IS_ERR(bh))
69 return bh;
70 inode->i_size += inode->i_sb->s_blocksize;
71 EXT4_I(inode)->i_disksize = inode->i_size;
72 BUFFER_TRACE(bh, "get_write_access");
73 err = ext4_journal_get_write_access(handle, bh);
74 if (err) {
75 brelse(bh);
76 ext4_std_error(inode->i_sb, err);
77 return ERR_PTR(err);
78 }
79 return bh;
80 }
81
82 static int ext4_dx_csum_verify(struct inode *inode,
83 struct ext4_dir_entry *dirent);
84
85 typedef enum {
86 EITHER, INDEX, DIRENT
87 } dirblock_type_t;
88
89 #define ext4_read_dirblock(inode, block, type) \
90 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__)
91
92 static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
93 ext4_lblk_t block,
94 dirblock_type_t type,
95 const char *func,
96 unsigned int line)
97 {
98 struct buffer_head *bh;
99 struct ext4_dir_entry *dirent;
100 int is_dx_block = 0;
101
102 bh = ext4_bread(NULL, inode, block, 0);
103 if (IS_ERR(bh)) {
104 __ext4_warning(inode->i_sb, func, line,
105 "inode #%lu: lblock %lu: comm %s: "
106 "error %ld reading directory block",
107 inode->i_ino, (unsigned long)block,
108 current->comm, PTR_ERR(bh));
109
110 return bh;
111 }
112 if (!bh) {
113 ext4_error_inode(inode, func, line, block,
114 "Directory hole found");
115 return ERR_PTR(-EFSCORRUPTED);
116 }
117 dirent = (struct ext4_dir_entry *) bh->b_data;
118 /* Determine whether or not we have an index block */
119 if (is_dx(inode)) {
120 if (block == 0)
121 is_dx_block = 1;
122 else if (ext4_rec_len_from_disk(dirent->rec_len,
123 inode->i_sb->s_blocksize) ==
124 inode->i_sb->s_blocksize)
125 is_dx_block = 1;
126 }
127 if (!is_dx_block && type == INDEX) {
128 ext4_error_inode(inode, func, line, block,
129 "directory leaf block found instead of index block");
130 brelse(bh);
131 return ERR_PTR(-EFSCORRUPTED);
132 }
133 if (!ext4_has_metadata_csum(inode->i_sb) ||
134 buffer_verified(bh))
135 return bh;
136
137 /*
138 * An empty leaf block can get mistaken for a index block; for
139 * this reason, we can only check the index checksum when the
140 * caller is sure it should be an index block.
141 */
142 if (is_dx_block && type == INDEX) {
143 if (ext4_dx_csum_verify(inode, dirent))
144 set_buffer_verified(bh);
145 else {
146 ext4_error_inode(inode, func, line, block,
147 "Directory index failed checksum");
148 brelse(bh);
149 return ERR_PTR(-EFSBADCRC);
150 }
151 }
152 if (!is_dx_block) {
153 if (ext4_dirent_csum_verify(inode, dirent))
154 set_buffer_verified(bh);
155 else {
156 ext4_error_inode(inode, func, line, block,
157 "Directory block failed checksum");
158 brelse(bh);
159 return ERR_PTR(-EFSBADCRC);
160 }
161 }
162 return bh;
163 }
164
165 #ifndef assert
166 #define assert(test) J_ASSERT(test)
167 #endif
168
169 #ifdef DX_DEBUG
170 #define dxtrace(command) command
171 #else
172 #define dxtrace(command)
173 #endif
174
175 struct fake_dirent
176 {
177 __le32 inode;
178 __le16 rec_len;
179 u8 name_len;
180 u8 file_type;
181 };
182
183 struct dx_countlimit
184 {
185 __le16 limit;
186 __le16 count;
187 };
188
189 struct dx_entry
190 {
191 __le32 hash;
192 __le32 block;
193 };
194
195 /*
196 * dx_root_info is laid out so that if it should somehow get overlaid by a
197 * dirent the two low bits of the hash version will be zero. Therefore, the
198 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
199 */
200
201 struct dx_root
202 {
203 struct fake_dirent dot;
204 char dot_name[4];
205 struct fake_dirent dotdot;
206 char dotdot_name[4];
207 struct dx_root_info
208 {
209 __le32 reserved_zero;
210 u8 hash_version;
211 u8 info_length; /* 8 */
212 u8 indirect_levels;
213 u8 unused_flags;
214 }
215 info;
216 struct dx_entry entries[0];
217 };
218
219 struct dx_node
220 {
221 struct fake_dirent fake;
222 struct dx_entry entries[0];
223 };
224
225
226 struct dx_frame
227 {
228 struct buffer_head *bh;
229 struct dx_entry *entries;
230 struct dx_entry *at;
231 };
232
233 struct dx_map_entry
234 {
235 u32 hash;
236 u16 offs;
237 u16 size;
238 };
239
240 /*
241 * This goes at the end of each htree block.
242 */
243 struct dx_tail {
244 u32 dt_reserved;
245 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
246 };
247
248 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
249 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
250 static inline unsigned dx_get_hash(struct dx_entry *entry);
251 static void dx_set_hash(struct dx_entry *entry, unsigned value);
252 static unsigned dx_get_count(struct dx_entry *entries);
253 static unsigned dx_get_limit(struct dx_entry *entries);
254 static void dx_set_count(struct dx_entry *entries, unsigned value);
255 static void dx_set_limit(struct dx_entry *entries, unsigned value);
256 static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
257 static unsigned dx_node_limit(struct inode *dir);
258 static struct dx_frame *dx_probe(struct ext4_filename *fname,
259 struct inode *dir,
260 struct dx_hash_info *hinfo,
261 struct dx_frame *frame);
262 static void dx_release(struct dx_frame *frames);
263 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
264 unsigned blocksize, struct dx_hash_info *hinfo,
265 struct dx_map_entry map[]);
266 static void dx_sort_map(struct dx_map_entry *map, unsigned count);
267 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
268 struct dx_map_entry *offsets, int count, unsigned blocksize);
269 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
270 static void dx_insert_block(struct dx_frame *frame,
271 u32 hash, ext4_lblk_t block);
272 static int ext4_htree_next_block(struct inode *dir, __u32 hash,
273 struct dx_frame *frame,
274 struct dx_frame *frames,
275 __u32 *start_hash);
276 static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
277 struct ext4_filename *fname,
278 struct ext4_dir_entry_2 **res_dir);
279 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
280 struct inode *dir, struct inode *inode);
281
282 /* checksumming functions */
283 void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
284 unsigned int blocksize)
285 {
286 memset(t, 0, sizeof(struct ext4_dir_entry_tail));
287 t->det_rec_len = ext4_rec_len_to_disk(
288 sizeof(struct ext4_dir_entry_tail), blocksize);
289 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
290 }
291
292 /* Walk through a dirent block to find a checksum "dirent" at the tail */
293 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
294 struct ext4_dir_entry *de)
295 {
296 struct ext4_dir_entry_tail *t;
297
298 #ifdef PARANOID
299 struct ext4_dir_entry *d, *top;
300
301 d = de;
302 top = (struct ext4_dir_entry *)(((void *)de) +
303 (EXT4_BLOCK_SIZE(inode->i_sb) -
304 sizeof(struct ext4_dir_entry_tail)));
305 while (d < top && d->rec_len)
306 d = (struct ext4_dir_entry *)(((void *)d) +
307 le16_to_cpu(d->rec_len));
308
309 if (d != top)
310 return NULL;
311
312 t = (struct ext4_dir_entry_tail *)d;
313 #else
314 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
315 #endif
316
317 if (t->det_reserved_zero1 ||
318 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
319 t->det_reserved_zero2 ||
320 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
321 return NULL;
322
323 return t;
324 }
325
326 static __le32 ext4_dirent_csum(struct inode *inode,
327 struct ext4_dir_entry *dirent, int size)
328 {
329 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
330 struct ext4_inode_info *ei = EXT4_I(inode);
331 __u32 csum;
332
333 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
334 return cpu_to_le32(csum);
335 }
336
337 #define warn_no_space_for_csum(inode) \
338 __warn_no_space_for_csum((inode), __func__, __LINE__)
339
340 static void __warn_no_space_for_csum(struct inode *inode, const char *func,
341 unsigned int line)
342 {
343 __ext4_warning_inode(inode, func, line,
344 "No space for directory leaf checksum. Please run e2fsck -D.");
345 }
346
347 int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
348 {
349 struct ext4_dir_entry_tail *t;
350
351 if (!ext4_has_metadata_csum(inode->i_sb))
352 return 1;
353
354 t = get_dirent_tail(inode, dirent);
355 if (!t) {
356 warn_no_space_for_csum(inode);
357 return 0;
358 }
359
360 if (t->det_checksum != ext4_dirent_csum(inode, dirent,
361 (void *)t - (void *)dirent))
362 return 0;
363
364 return 1;
365 }
366
367 static void ext4_dirent_csum_set(struct inode *inode,
368 struct ext4_dir_entry *dirent)
369 {
370 struct ext4_dir_entry_tail *t;
371
372 if (!ext4_has_metadata_csum(inode->i_sb))
373 return;
374
375 t = get_dirent_tail(inode, dirent);
376 if (!t) {
377 warn_no_space_for_csum(inode);
378 return;
379 }
380
381 t->det_checksum = ext4_dirent_csum(inode, dirent,
382 (void *)t - (void *)dirent);
383 }
384
385 int ext4_handle_dirty_dirent_node(handle_t *handle,
386 struct inode *inode,
387 struct buffer_head *bh)
388 {
389 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
390 return ext4_handle_dirty_metadata(handle, inode, bh);
391 }
392
393 static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
394 struct ext4_dir_entry *dirent,
395 int *offset)
396 {
397 struct ext4_dir_entry *dp;
398 struct dx_root_info *root;
399 int count_offset;
400
401 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
402 count_offset = 8;
403 else if (le16_to_cpu(dirent->rec_len) == 12) {
404 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
405 if (le16_to_cpu(dp->rec_len) !=
406 EXT4_BLOCK_SIZE(inode->i_sb) - 12)
407 return NULL;
408 root = (struct dx_root_info *)(((void *)dp + 12));
409 if (root->reserved_zero ||
410 root->info_length != sizeof(struct dx_root_info))
411 return NULL;
412 count_offset = 32;
413 } else
414 return NULL;
415
416 if (offset)
417 *offset = count_offset;
418 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
419 }
420
421 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
422 int count_offset, int count, struct dx_tail *t)
423 {
424 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
425 struct ext4_inode_info *ei = EXT4_I(inode);
426 __u32 csum;
427 int size;
428 __u32 dummy_csum = 0;
429 int offset = offsetof(struct dx_tail, dt_checksum);
430
431 size = count_offset + (count * sizeof(struct dx_entry));
432 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
433 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset);
434 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
435
436 return cpu_to_le32(csum);
437 }
438
439 static int ext4_dx_csum_verify(struct inode *inode,
440 struct ext4_dir_entry *dirent)
441 {
442 struct dx_countlimit *c;
443 struct dx_tail *t;
444 int count_offset, limit, count;
445
446 if (!ext4_has_metadata_csum(inode->i_sb))
447 return 1;
448
449 c = get_dx_countlimit(inode, dirent, &count_offset);
450 if (!c) {
451 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
452 return 0;
453 }
454 limit = le16_to_cpu(c->limit);
455 count = le16_to_cpu(c->count);
456 if (count_offset + (limit * sizeof(struct dx_entry)) >
457 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
458 warn_no_space_for_csum(inode);
459 return 0;
460 }
461 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
462
463 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
464 count, t))
465 return 0;
466 return 1;
467 }
468
469 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
470 {
471 struct dx_countlimit *c;
472 struct dx_tail *t;
473 int count_offset, limit, count;
474
475 if (!ext4_has_metadata_csum(inode->i_sb))
476 return;
477
478 c = get_dx_countlimit(inode, dirent, &count_offset);
479 if (!c) {
480 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
481 return;
482 }
483 limit = le16_to_cpu(c->limit);
484 count = le16_to_cpu(c->count);
485 if (count_offset + (limit * sizeof(struct dx_entry)) >
486 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
487 warn_no_space_for_csum(inode);
488 return;
489 }
490 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
491
492 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
493 }
494
495 static inline int ext4_handle_dirty_dx_node(handle_t *handle,
496 struct inode *inode,
497 struct buffer_head *bh)
498 {
499 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
500 return ext4_handle_dirty_metadata(handle, inode, bh);
501 }
502
503 /*
504 * p is at least 6 bytes before the end of page
505 */
506 static inline struct ext4_dir_entry_2 *
507 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
508 {
509 return (struct ext4_dir_entry_2 *)((char *)p +
510 ext4_rec_len_from_disk(p->rec_len, blocksize));
511 }
512
513 /*
514 * Future: use high four bits of block for coalesce-on-delete flags
515 * Mask them off for now.
516 */
517
518 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
519 {
520 return le32_to_cpu(entry->block) & 0x0fffffff;
521 }
522
523 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
524 {
525 entry->block = cpu_to_le32(value);
526 }
527
528 static inline unsigned dx_get_hash(struct dx_entry *entry)
529 {
530 return le32_to_cpu(entry->hash);
531 }
532
533 static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
534 {
535 entry->hash = cpu_to_le32(value);
536 }
537
538 static inline unsigned dx_get_count(struct dx_entry *entries)
539 {
540 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
541 }
542
543 static inline unsigned dx_get_limit(struct dx_entry *entries)
544 {
545 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
546 }
547
548 static inline void dx_set_count(struct dx_entry *entries, unsigned value)
549 {
550 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
551 }
552
553 static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
554 {
555 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
556 }
557
558 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
559 {
560 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
561 EXT4_DIR_REC_LEN(2) - infosize;
562
563 if (ext4_has_metadata_csum(dir->i_sb))
564 entry_space -= sizeof(struct dx_tail);
565 return entry_space / sizeof(struct dx_entry);
566 }
567
568 static inline unsigned dx_node_limit(struct inode *dir)
569 {
570 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
571
572 if (ext4_has_metadata_csum(dir->i_sb))
573 entry_space -= sizeof(struct dx_tail);
574 return entry_space / sizeof(struct dx_entry);
575 }
576
577 /*
578 * Debug
579 */
580 #ifdef DX_DEBUG
581 static void dx_show_index(char * label, struct dx_entry *entries)
582 {
583 int i, n = dx_get_count (entries);
584 printk(KERN_DEBUG "%s index", label);
585 for (i = 0; i < n; i++) {
586 printk(KERN_CONT " %x->%lu",
587 i ? dx_get_hash(entries + i) : 0,
588 (unsigned long)dx_get_block(entries + i));
589 }
590 printk(KERN_CONT "\n");
591 }
592
593 struct stats
594 {
595 unsigned names;
596 unsigned space;
597 unsigned bcount;
598 };
599
600 static struct stats dx_show_leaf(struct inode *dir,
601 struct dx_hash_info *hinfo,
602 struct ext4_dir_entry_2 *de,
603 int size, int show_names)
604 {
605 unsigned names = 0, space = 0;
606 char *base = (char *) de;
607 struct dx_hash_info h = *hinfo;
608
609 printk("names: ");
610 while ((char *) de < base + size)
611 {
612 if (de->inode)
613 {
614 if (show_names)
615 {
616 #ifdef CONFIG_FS_ENCRYPTION
617 int len;
618 char *name;
619 struct fscrypt_str fname_crypto_str =
620 FSTR_INIT(NULL, 0);
621 int res = 0;
622
623 name = de->name;
624 len = de->name_len;
625 if (IS_ENCRYPTED(dir))
626 res = fscrypt_get_encryption_info(dir);
627 if (res) {
628 printk(KERN_WARNING "Error setting up"
629 " fname crypto: %d\n", res);
630 }
631 if (!fscrypt_has_encryption_key(dir)) {
632 /* Directory is not encrypted */
633 ext4fs_dirhash(dir, de->name,
634 de->name_len, &h);
635 printk("%*.s:(U)%x.%u ", len,
636 name, h.hash,
637 (unsigned) ((char *) de
638 - base));
639 } else {
640 struct fscrypt_str de_name =
641 FSTR_INIT(name, len);
642
643 /* Directory is encrypted */
644 res = fscrypt_fname_alloc_buffer(
645 dir, len,
646 &fname_crypto_str);
647 if (res)
648 printk(KERN_WARNING "Error "
649 "allocating crypto "
650 "buffer--skipping "
651 "crypto\n");
652 res = fscrypt_fname_disk_to_usr(dir,
653 0, 0, &de_name,
654 &fname_crypto_str);
655 if (res) {
656 printk(KERN_WARNING "Error "
657 "converting filename "
658 "from disk to usr"
659 "\n");
660 name = "??";
661 len = 2;
662 } else {
663 name = fname_crypto_str.name;
664 len = fname_crypto_str.len;
665 }
666 ext4fs_dirhash(dir, de->name,
667 de->name_len, &h);
668 printk("%*.s:(E)%x.%u ", len, name,
669 h.hash, (unsigned) ((char *) de
670 - base));
671 fscrypt_fname_free_buffer(
672 &fname_crypto_str);
673 }
674 #else
675 int len = de->name_len;
676 char *name = de->name;
677 ext4fs_dirhash(dir, de->name, de->name_len, &h);
678 printk("%*.s:%x.%u ", len, name, h.hash,
679 (unsigned) ((char *) de - base));
680 #endif
681 }
682 space += EXT4_DIR_REC_LEN(de->name_len);
683 names++;
684 }
685 de = ext4_next_entry(de, size);
686 }
687 printk(KERN_CONT "(%i)\n", names);
688 return (struct stats) { names, space, 1 };
689 }
690
691 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
692 struct dx_entry *entries, int levels)
693 {
694 unsigned blocksize = dir->i_sb->s_blocksize;
695 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
696 unsigned bcount = 0;
697 struct buffer_head *bh;
698 printk("%i indexed blocks...\n", count);
699 for (i = 0; i < count; i++, entries++)
700 {
701 ext4_lblk_t block = dx_get_block(entries);
702 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
703 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
704 struct stats stats;
705 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
706 bh = ext4_bread(NULL,dir, block, 0);
707 if (!bh || IS_ERR(bh))
708 continue;
709 stats = levels?
710 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
711 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)
712 bh->b_data, blocksize, 0);
713 names += stats.names;
714 space += stats.space;
715 bcount += stats.bcount;
716 brelse(bh);
717 }
718 if (bcount)
719 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
720 levels ? "" : " ", names, space/bcount,
721 (space/bcount)*100/blocksize);
722 return (struct stats) { names, space, bcount};
723 }
724 #endif /* DX_DEBUG */
725
726 /*
727 * Probe for a directory leaf block to search.
728 *
729 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
730 * error in the directory index, and the caller should fall back to
731 * searching the directory normally. The callers of dx_probe **MUST**
732 * check for this error code, and make sure it never gets reflected
733 * back to userspace.
734 */
735 static struct dx_frame *
736 dx_probe(struct ext4_filename *fname, struct inode *dir,
737 struct dx_hash_info *hinfo, struct dx_frame *frame_in)
738 {
739 unsigned count, indirect;
740 struct dx_entry *at, *entries, *p, *q, *m;
741 struct dx_root *root;
742 struct dx_frame *frame = frame_in;
743 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);
744 u32 hash;
745
746 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0]));
747 frame->bh = ext4_read_dirblock(dir, 0, INDEX);
748 if (IS_ERR(frame->bh))
749 return (struct dx_frame *) frame->bh;
750
751 root = (struct dx_root *) frame->bh->b_data;
752 if (root->info.hash_version != DX_HASH_TEA &&
753 root->info.hash_version != DX_HASH_HALF_MD4 &&
754 root->info.hash_version != DX_HASH_LEGACY) {
755 ext4_warning_inode(dir, "Unrecognised inode hash code %u",
756 root->info.hash_version);
757 goto fail;
758 }
759 if (fname)
760 hinfo = &fname->hinfo;
761 hinfo->hash_version = root->info.hash_version;
762 if (hinfo->hash_version <= DX_HASH_TEA)
763 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
764 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
765 if (fname && fname_name(fname))
766 ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), hinfo);
767 hash = hinfo->hash;
768
769 if (root->info.unused_flags & 1) {
770 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x",
771 root->info.unused_flags);
772 goto fail;
773 }
774
775 indirect = root->info.indirect_levels;
776 if (indirect >= ext4_dir_htree_level(dir->i_sb)) {
777 ext4_warning(dir->i_sb,
778 "Directory (ino: %lu) htree depth %#06x exceed"
779 "supported value", dir->i_ino,
780 ext4_dir_htree_level(dir->i_sb));
781 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) {
782 ext4_warning(dir->i_sb, "Enable large directory "
783 "feature to access it");
784 }
785 goto fail;
786 }
787
788 entries = (struct dx_entry *)(((char *)&root->info) +
789 root->info.info_length);
790
791 if (dx_get_limit(entries) != dx_root_limit(dir,
792 root->info.info_length)) {
793 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
794 dx_get_limit(entries),
795 dx_root_limit(dir, root->info.info_length));
796 goto fail;
797 }
798
799 dxtrace(printk("Look up %x", hash));
800 while (1) {
801 count = dx_get_count(entries);
802 if (!count || count > dx_get_limit(entries)) {
803 ext4_warning_inode(dir,
804 "dx entry: count %u beyond limit %u",
805 count, dx_get_limit(entries));
806 goto fail;
807 }
808
809 p = entries + 1;
810 q = entries + count - 1;
811 while (p <= q) {
812 m = p + (q - p) / 2;
813 dxtrace(printk(KERN_CONT "."));
814 if (dx_get_hash(m) > hash)
815 q = m - 1;
816 else
817 p = m + 1;
818 }
819
820 if (0) { // linear search cross check
821 unsigned n = count - 1;
822 at = entries;
823 while (n--)
824 {
825 dxtrace(printk(KERN_CONT ","));
826 if (dx_get_hash(++at) > hash)
827 {
828 at--;
829 break;
830 }
831 }
832 assert (at == p - 1);
833 }
834
835 at = p - 1;
836 dxtrace(printk(KERN_CONT " %x->%u\n",
837 at == entries ? 0 : dx_get_hash(at),
838 dx_get_block(at)));
839 frame->entries = entries;
840 frame->at = at;
841 if (!indirect--)
842 return frame;
843 frame++;
844 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
845 if (IS_ERR(frame->bh)) {
846 ret_err = (struct dx_frame *) frame->bh;
847 frame->bh = NULL;
848 goto fail;
849 }
850 entries = ((struct dx_node *) frame->bh->b_data)->entries;
851
852 if (dx_get_limit(entries) != dx_node_limit(dir)) {
853 ext4_warning_inode(dir,
854 "dx entry: limit %u != node limit %u",
855 dx_get_limit(entries), dx_node_limit(dir));
856 goto fail;
857 }
858 }
859 fail:
860 while (frame >= frame_in) {
861 brelse(frame->bh);
862 frame--;
863 }
864
865 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
866 ext4_warning_inode(dir,
867 "Corrupt directory, running e2fsck is recommended");
868 return ret_err;
869 }
870
871 static void dx_release(struct dx_frame *frames)
872 {
873 struct dx_root_info *info;
874 int i;
875 unsigned int indirect_levels;
876
877 if (frames[0].bh == NULL)
878 return;
879
880 info = &((struct dx_root *)frames[0].bh->b_data)->info;
881 /* save local copy, "info" may be freed after brelse() */
882 indirect_levels = info->indirect_levels;
883 for (i = 0; i <= indirect_levels; i++) {
884 if (frames[i].bh == NULL)
885 break;
886 brelse(frames[i].bh);
887 frames[i].bh = NULL;
888 }
889 }
890
891 /*
892 * This function increments the frame pointer to search the next leaf
893 * block, and reads in the necessary intervening nodes if the search
894 * should be necessary. Whether or not the search is necessary is
895 * controlled by the hash parameter. If the hash value is even, then
896 * the search is only continued if the next block starts with that
897 * hash value. This is used if we are searching for a specific file.
898 *
899 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
900 *
901 * This function returns 1 if the caller should continue to search,
902 * or 0 if it should not. If there is an error reading one of the
903 * index blocks, it will a negative error code.
904 *
905 * If start_hash is non-null, it will be filled in with the starting
906 * hash of the next page.
907 */
908 static int ext4_htree_next_block(struct inode *dir, __u32 hash,
909 struct dx_frame *frame,
910 struct dx_frame *frames,
911 __u32 *start_hash)
912 {
913 struct dx_frame *p;
914 struct buffer_head *bh;
915 int num_frames = 0;
916 __u32 bhash;
917
918 p = frame;
919 /*
920 * Find the next leaf page by incrementing the frame pointer.
921 * If we run out of entries in the interior node, loop around and
922 * increment pointer in the parent node. When we break out of
923 * this loop, num_frames indicates the number of interior
924 * nodes need to be read.
925 */
926 while (1) {
927 if (++(p->at) < p->entries + dx_get_count(p->entries))
928 break;
929 if (p == frames)
930 return 0;
931 num_frames++;
932 p--;
933 }
934
935 /*
936 * If the hash is 1, then continue only if the next page has a
937 * continuation hash of any value. This is used for readdir
938 * handling. Otherwise, check to see if the hash matches the
939 * desired contiuation hash. If it doesn't, return since
940 * there's no point to read in the successive index pages.
941 */
942 bhash = dx_get_hash(p->at);
943 if (start_hash)
944 *start_hash = bhash;
945 if ((hash & 1) == 0) {
946 if ((bhash & ~1) != hash)
947 return 0;
948 }
949 /*
950 * If the hash is HASH_NB_ALWAYS, we always go to the next
951 * block so no check is necessary
952 */
953 while (num_frames--) {
954 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
955 if (IS_ERR(bh))
956 return PTR_ERR(bh);
957 p++;
958 brelse(p->bh);
959 p->bh = bh;
960 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
961 }
962 return 1;
963 }
964
965
966 /*
967 * This function fills a red-black tree with information from a
968 * directory block. It returns the number directory entries loaded
969 * into the tree. If there is an error it is returned in err.
970 */
971 static int htree_dirblock_to_tree(struct file *dir_file,
972 struct inode *dir, ext4_lblk_t block,
973 struct dx_hash_info *hinfo,
974 __u32 start_hash, __u32 start_minor_hash)
975 {
976 struct buffer_head *bh;
977 struct ext4_dir_entry_2 *de, *top;
978 int err = 0, count = 0;
979 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;
980
981 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
982 (unsigned long)block));
983 bh = ext4_read_dirblock(dir, block, DIRENT);
984 if (IS_ERR(bh))
985 return PTR_ERR(bh);
986
987 de = (struct ext4_dir_entry_2 *) bh->b_data;
988 top = (struct ext4_dir_entry_2 *) ((char *) de +
989 dir->i_sb->s_blocksize -
990 EXT4_DIR_REC_LEN(0));
991 #ifdef CONFIG_FS_ENCRYPTION
992 /* Check if the directory is encrypted */
993 if (IS_ENCRYPTED(dir)) {
994 err = fscrypt_get_encryption_info(dir);
995 if (err < 0) {
996 brelse(bh);
997 return err;
998 }
999 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN,
1000 &fname_crypto_str);
1001 if (err < 0) {
1002 brelse(bh);
1003 return err;
1004 }
1005 }
1006 #endif
1007 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
1008 if (ext4_check_dir_entry(dir, NULL, de, bh,
1009 bh->b_data, bh->b_size,
1010 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
1011 + ((char *)de - bh->b_data))) {
1012 /* silently ignore the rest of the block */
1013 break;
1014 }
1015 ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
1016 if ((hinfo->hash < start_hash) ||
1017 ((hinfo->hash == start_hash) &&
1018 (hinfo->minor_hash < start_minor_hash)))
1019 continue;
1020 if (de->inode == 0)
1021 continue;
1022 if (!IS_ENCRYPTED(dir)) {
1023 tmp_str.name = de->name;
1024 tmp_str.len = de->name_len;
1025 err = ext4_htree_store_dirent(dir_file,
1026 hinfo->hash, hinfo->minor_hash, de,
1027 &tmp_str);
1028 } else {
1029 int save_len = fname_crypto_str.len;
1030 struct fscrypt_str de_name = FSTR_INIT(de->name,
1031 de->name_len);
1032
1033 /* Directory is encrypted */
1034 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash,
1035 hinfo->minor_hash, &de_name,
1036 &fname_crypto_str);
1037 if (err) {
1038 count = err;
1039 goto errout;
1040 }
1041 err = ext4_htree_store_dirent(dir_file,
1042 hinfo->hash, hinfo->minor_hash, de,
1043 &fname_crypto_str);
1044 fname_crypto_str.len = save_len;
1045 }
1046 if (err != 0) {
1047 count = err;
1048 goto errout;
1049 }
1050 count++;
1051 }
1052 errout:
1053 brelse(bh);
1054 #ifdef CONFIG_FS_ENCRYPTION
1055 fscrypt_fname_free_buffer(&fname_crypto_str);
1056 #endif
1057 return count;
1058 }
1059
1060
1061 /*
1062 * This function fills a red-black tree with information from a
1063 * directory. We start scanning the directory in hash order, starting
1064 * at start_hash and start_minor_hash.
1065 *
1066 * This function returns the number of entries inserted into the tree,
1067 * or a negative error code.
1068 */
1069 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1070 __u32 start_minor_hash, __u32 *next_hash)
1071 {
1072 struct dx_hash_info hinfo;
1073 struct ext4_dir_entry_2 *de;
1074 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1075 struct inode *dir;
1076 ext4_lblk_t block;
1077 int count = 0;
1078 int ret, err;
1079 __u32 hashval;
1080 struct fscrypt_str tmp_str;
1081
1082 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
1083 start_hash, start_minor_hash));
1084 dir = file_inode(dir_file);
1085 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
1086 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
1087 if (hinfo.hash_version <= DX_HASH_TEA)
1088 hinfo.hash_version +=
1089 EXT4_SB(dir->i_sb)->s_hash_unsigned;
1090 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1091 if (ext4_has_inline_data(dir)) {
1092 int has_inline_data = 1;
1093 count = htree_inlinedir_to_tree(dir_file, dir, 0,
1094 &hinfo, start_hash,
1095 start_minor_hash,
1096 &has_inline_data);
1097 if (has_inline_data) {
1098 *next_hash = ~0;
1099 return count;
1100 }
1101 }
1102 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
1103 start_hash, start_minor_hash);
1104 *next_hash = ~0;
1105 return count;
1106 }
1107 hinfo.hash = start_hash;
1108 hinfo.minor_hash = 0;
1109 frame = dx_probe(NULL, dir, &hinfo, frames);
1110 if (IS_ERR(frame))
1111 return PTR_ERR(frame);
1112
1113 /* Add '.' and '..' from the htree header */
1114 if (!start_hash && !start_minor_hash) {
1115 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1116 tmp_str.name = de->name;
1117 tmp_str.len = de->name_len;
1118 err = ext4_htree_store_dirent(dir_file, 0, 0,
1119 de, &tmp_str);
1120 if (err != 0)
1121 goto errout;
1122 count++;
1123 }
1124 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
1125 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1126 de = ext4_next_entry(de, dir->i_sb->s_blocksize);
1127 tmp_str.name = de->name;
1128 tmp_str.len = de->name_len;
1129 err = ext4_htree_store_dirent(dir_file, 2, 0,
1130 de, &tmp_str);
1131 if (err != 0)
1132 goto errout;
1133 count++;
1134 }
1135
1136 while (1) {
1137 if (fatal_signal_pending(current)) {
1138 err = -ERESTARTSYS;
1139 goto errout;
1140 }
1141 cond_resched();
1142 block = dx_get_block(frame->at);
1143 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
1144 start_hash, start_minor_hash);
1145 if (ret < 0) {
1146 err = ret;
1147 goto errout;
1148 }
1149 count += ret;
1150 hashval = ~0;
1151 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
1152 frame, frames, &hashval);
1153 *next_hash = hashval;
1154 if (ret < 0) {
1155 err = ret;
1156 goto errout;
1157 }
1158 /*
1159 * Stop if: (a) there are no more entries, or
1160 * (b) we have inserted at least one entry and the
1161 * next hash value is not a continuation
1162 */
1163 if ((ret == 0) ||
1164 (count && ((hashval & 1) == 0)))
1165 break;
1166 }
1167 dx_release(frames);
1168 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1169 "next hash: %x\n", count, *next_hash));
1170 return count;
1171 errout:
1172 dx_release(frames);
1173 return (err);
1174 }
1175
1176 static inline int search_dirblock(struct buffer_head *bh,
1177 struct inode *dir,
1178 struct ext4_filename *fname,
1179 unsigned int offset,
1180 struct ext4_dir_entry_2 **res_dir)
1181 {
1182 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,
1183 fname, offset, res_dir);
1184 }
1185
1186 /*
1187 * Directory block splitting, compacting
1188 */
1189
1190 /*
1191 * Create map of hash values, offsets, and sizes, stored at end of block.
1192 * Returns number of entries mapped.
1193 */
1194 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
1195 unsigned blocksize, struct dx_hash_info *hinfo,
1196 struct dx_map_entry *map_tail)
1197 {
1198 int count = 0;
1199 char *base = (char *) de;
1200 struct dx_hash_info h = *hinfo;
1201
1202 while ((char *) de < base + blocksize) {
1203 if (de->name_len && de->inode) {
1204 ext4fs_dirhash(dir, de->name, de->name_len, &h);
1205 map_tail--;
1206 map_tail->hash = h.hash;
1207 map_tail->offs = ((char *) de - base)>>2;
1208 map_tail->size = le16_to_cpu(de->rec_len);
1209 count++;
1210 cond_resched();
1211 }
1212 /* XXX: do we need to check rec_len == 0 case? -Chris */
1213 de = ext4_next_entry(de, blocksize);
1214 }
1215 return count;
1216 }
1217
1218 /* Sort map by hash value */
1219 static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1220 {
1221 struct dx_map_entry *p, *q, *top = map + count - 1;
1222 int more;
1223 /* Combsort until bubble sort doesn't suck */
1224 while (count > 2) {
1225 count = count*10/13;
1226 if (count - 9 < 2) /* 9, 10 -> 11 */
1227 count = 11;
1228 for (p = top, q = p - count; q >= map; p--, q--)
1229 if (p->hash < q->hash)
1230 swap(*p, *q);
1231 }
1232 /* Garden variety bubble sort */
1233 do {
1234 more = 0;
1235 q = top;
1236 while (q-- > map) {
1237 if (q[1].hash >= q[0].hash)
1238 continue;
1239 swap(*(q+1), *q);
1240 more = 1;
1241 }
1242 } while(more);
1243 }
1244
1245 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
1246 {
1247 struct dx_entry *entries = frame->entries;
1248 struct dx_entry *old = frame->at, *new = old + 1;
1249 int count = dx_get_count(entries);
1250
1251 assert(count < dx_get_limit(entries));
1252 assert(old < entries + count);
1253 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1254 dx_set_hash(new, hash);
1255 dx_set_block(new, block);
1256 dx_set_count(entries, count + 1);
1257 }
1258
1259 #ifdef CONFIG_UNICODE
1260 /*
1261 * Test whether a case-insensitive directory entry matches the filename
1262 * being searched for.
1263 *
1264 * Returns: 0 if the directory entry matches, more than 0 if it
1265 * doesn't match or less than zero on error.
1266 */
1267 int ext4_ci_compare(const struct inode *parent, const struct qstr *name,
1268 const struct qstr *entry)
1269 {
1270 const struct ext4_sb_info *sbi = EXT4_SB(parent->i_sb);
1271 const struct unicode_map *um = sbi->s_encoding;
1272 int ret;
1273
1274 ret = utf8_strncasecmp(um, name, entry);
1275 if (ret < 0) {
1276 /* Handle invalid character sequence as either an error
1277 * or as an opaque byte sequence.
1278 */
1279 if (ext4_has_strict_mode(sbi))
1280 return -EINVAL;
1281
1282 if (name->len != entry->len)
1283 return 1;
1284
1285 return !!memcmp(name->name, entry->name, name->len);
1286 }
1287
1288 return ret;
1289 }
1290 #endif
1291
1292 /*
1293 * Test whether a directory entry matches the filename being searched for.
1294 *
1295 * Return: %true if the directory entry matches, otherwise %false.
1296 */
1297 static inline bool ext4_match(const struct inode *parent,
1298 const struct ext4_filename *fname,
1299 const struct ext4_dir_entry_2 *de)
1300 {
1301 struct fscrypt_name f;
1302 #ifdef CONFIG_UNICODE
1303 const struct qstr entry = {.name = de->name, .len = de->name_len};
1304 #endif
1305
1306 if (!de->inode)
1307 return false;
1308
1309 f.usr_fname = fname->usr_fname;
1310 f.disk_name = fname->disk_name;
1311 #ifdef CONFIG_FS_ENCRYPTION
1312 f.crypto_buf = fname->crypto_buf;
1313 #endif
1314
1315 #ifdef CONFIG_UNICODE
1316 if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent))
1317 return (ext4_ci_compare(parent, fname->usr_fname, &entry) == 0);
1318 #endif
1319
1320 return fscrypt_match_name(&f, de->name, de->name_len);
1321 }
1322
1323 /*
1324 * Returns 0 if not found, -1 on failure, and 1 on success
1325 */
1326 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
1327 struct inode *dir, struct ext4_filename *fname,
1328 unsigned int offset, struct ext4_dir_entry_2 **res_dir)
1329 {
1330 struct ext4_dir_entry_2 * de;
1331 char * dlimit;
1332 int de_len;
1333
1334 de = (struct ext4_dir_entry_2 *)search_buf;
1335 dlimit = search_buf + buf_size;
1336 while ((char *) de < dlimit) {
1337 /* this code is executed quadratically often */
1338 /* do minimal checking `by hand' */
1339 if ((char *) de + de->name_len <= dlimit &&
1340 ext4_match(dir, fname, de)) {
1341 /* found a match - just to be sure, do
1342 * a full check */
1343 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
1344 bh->b_size, offset))
1345 return -1;
1346 *res_dir = de;
1347 return 1;
1348 }
1349 /* prevent looping on a bad block */
1350 de_len = ext4_rec_len_from_disk(de->rec_len,
1351 dir->i_sb->s_blocksize);
1352 if (de_len <= 0)
1353 return -1;
1354 offset += de_len;
1355 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1356 }
1357 return 0;
1358 }
1359
1360 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1361 struct ext4_dir_entry *de)
1362 {
1363 struct super_block *sb = dir->i_sb;
1364
1365 if (!is_dx(dir))
1366 return 0;
1367 if (block == 0)
1368 return 1;
1369 if (de->inode == 0 &&
1370 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
1371 sb->s_blocksize)
1372 return 1;
1373 return 0;
1374 }
1375
1376 /*
1377 * __ext4_find_entry()
1378 *
1379 * finds an entry in the specified directory with the wanted name. It
1380 * returns the cache buffer in which the entry was found, and the entry
1381 * itself (as a parameter - res_dir). It does NOT read the inode of the
1382 * entry - you'll have to do that yourself if you want to.
1383 *
1384 * The returned buffer_head has ->b_count elevated. The caller is expected
1385 * to brelse() it when appropriate.
1386 */
1387 static struct buffer_head *__ext4_find_entry(struct inode *dir,
1388 struct ext4_filename *fname,
1389 struct ext4_dir_entry_2 **res_dir,
1390 int *inlined)
1391 {
1392 struct super_block *sb;
1393 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1394 struct buffer_head *bh, *ret = NULL;
1395 ext4_lblk_t start, block;
1396 const u8 *name = fname->usr_fname->name;
1397 size_t ra_max = 0; /* Number of bh's in the readahead
1398 buffer, bh_use[] */
1399 size_t ra_ptr = 0; /* Current index into readahead
1400 buffer */
1401 ext4_lblk_t nblocks;
1402 int i, namelen, retval;
1403
1404 *res_dir = NULL;
1405 sb = dir->i_sb;
1406 namelen = fname->usr_fname->len;
1407 if (namelen > EXT4_NAME_LEN)
1408 return NULL;
1409
1410 if (ext4_has_inline_data(dir)) {
1411 int has_inline_data = 1;
1412 ret = ext4_find_inline_entry(dir, fname, res_dir,
1413 &has_inline_data);
1414 if (has_inline_data) {
1415 if (inlined)
1416 *inlined = 1;
1417 goto cleanup_and_exit;
1418 }
1419 }
1420
1421 if ((namelen <= 2) && (name[0] == '.') &&
1422 (name[1] == '.' || name[1] == '\0')) {
1423 /*
1424 * "." or ".." will only be in the first block
1425 * NFS may look up ".."; "." should be handled by the VFS
1426 */
1427 block = start = 0;
1428 nblocks = 1;
1429 goto restart;
1430 }
1431 if (is_dx(dir)) {
1432 ret = ext4_dx_find_entry(dir, fname, res_dir);
1433 /*
1434 * On success, or if the error was file not found,
1435 * return. Otherwise, fall back to doing a search the
1436 * old fashioned way.
1437 */
1438 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR)
1439 goto cleanup_and_exit;
1440 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1441 "falling back\n"));
1442 ret = NULL;
1443 }
1444 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1445 if (!nblocks) {
1446 ret = NULL;
1447 goto cleanup_and_exit;
1448 }
1449 start = EXT4_I(dir)->i_dir_start_lookup;
1450 if (start >= nblocks)
1451 start = 0;
1452 block = start;
1453 restart:
1454 do {
1455 /*
1456 * We deal with the read-ahead logic here.
1457 */
1458 if (ra_ptr >= ra_max) {
1459 /* Refill the readahead buffer */
1460 ra_ptr = 0;
1461 if (block < start)
1462 ra_max = start - block;
1463 else
1464 ra_max = nblocks - block;
1465 ra_max = min(ra_max, ARRAY_SIZE(bh_use));
1466 retval = ext4_bread_batch(dir, block, ra_max,
1467 false /* wait */, bh_use);
1468 if (retval) {
1469 ret = ERR_PTR(retval);
1470 ra_max = 0;
1471 goto cleanup_and_exit;
1472 }
1473 }
1474 if ((bh = bh_use[ra_ptr++]) == NULL)
1475 goto next;
1476 wait_on_buffer(bh);
1477 if (!buffer_uptodate(bh)) {
1478 EXT4_ERROR_INODE(dir, "reading directory lblock %lu",
1479 (unsigned long) block);
1480 brelse(bh);
1481 ret = ERR_PTR(-EIO);
1482 goto cleanup_and_exit;
1483 }
1484 if (!buffer_verified(bh) &&
1485 !is_dx_internal_node(dir, block,
1486 (struct ext4_dir_entry *)bh->b_data) &&
1487 !ext4_dirent_csum_verify(dir,
1488 (struct ext4_dir_entry *)bh->b_data)) {
1489 EXT4_ERROR_INODE(dir, "checksumming directory "
1490 "block %lu", (unsigned long)block);
1491 brelse(bh);
1492 ret = ERR_PTR(-EFSBADCRC);
1493 goto cleanup_and_exit;
1494 }
1495 set_buffer_verified(bh);
1496 i = search_dirblock(bh, dir, fname,
1497 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
1498 if (i == 1) {
1499 EXT4_I(dir)->i_dir_start_lookup = block;
1500 ret = bh;
1501 goto cleanup_and_exit;
1502 } else {
1503 brelse(bh);
1504 if (i < 0)
1505 goto cleanup_and_exit;
1506 }
1507 next:
1508 if (++block >= nblocks)
1509 block = 0;
1510 } while (block != start);
1511
1512 /*
1513 * If the directory has grown while we were searching, then
1514 * search the last part of the directory before giving up.
1515 */
1516 block = nblocks;
1517 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1518 if (block < nblocks) {
1519 start = 0;
1520 goto restart;
1521 }
1522
1523 cleanup_and_exit:
1524 /* Clean up the read-ahead blocks */
1525 for (; ra_ptr < ra_max; ra_ptr++)
1526 brelse(bh_use[ra_ptr]);
1527 return ret;
1528 }
1529
1530 static struct buffer_head *ext4_find_entry(struct inode *dir,
1531 const struct qstr *d_name,
1532 struct ext4_dir_entry_2 **res_dir,
1533 int *inlined)
1534 {
1535 int err;
1536 struct ext4_filename fname;
1537 struct buffer_head *bh;
1538
1539 err = ext4_fname_setup_filename(dir, d_name, 1, &fname);
1540 if (err == -ENOENT)
1541 return NULL;
1542 if (err)
1543 return ERR_PTR(err);
1544
1545 bh = __ext4_find_entry(dir, &fname, res_dir, inlined);
1546
1547 ext4_fname_free_filename(&fname);
1548 return bh;
1549 }
1550
1551 static struct buffer_head *ext4_lookup_entry(struct inode *dir,
1552 struct dentry *dentry,
1553 struct ext4_dir_entry_2 **res_dir)
1554 {
1555 int err;
1556 struct ext4_filename fname;
1557 struct buffer_head *bh;
1558
1559 err = ext4_fname_prepare_lookup(dir, dentry, &fname);
1560 if (err == -ENOENT)
1561 return NULL;
1562 if (err)
1563 return ERR_PTR(err);
1564
1565 bh = __ext4_find_entry(dir, &fname, res_dir, NULL);
1566
1567 ext4_fname_free_filename(&fname);
1568 return bh;
1569 }
1570
1571 static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
1572 struct ext4_filename *fname,
1573 struct ext4_dir_entry_2 **res_dir)
1574 {
1575 struct super_block * sb = dir->i_sb;
1576 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1577 struct buffer_head *bh;
1578 ext4_lblk_t block;
1579 int retval;
1580
1581 #ifdef CONFIG_FS_ENCRYPTION
1582 *res_dir = NULL;
1583 #endif
1584 frame = dx_probe(fname, dir, NULL, frames);
1585 if (IS_ERR(frame))
1586 return (struct buffer_head *) frame;
1587 do {
1588 block = dx_get_block(frame->at);
1589 bh = ext4_read_dirblock(dir, block, DIRENT);
1590 if (IS_ERR(bh))
1591 goto errout;
1592
1593 retval = search_dirblock(bh, dir, fname,
1594 block << EXT4_BLOCK_SIZE_BITS(sb),
1595 res_dir);
1596 if (retval == 1)
1597 goto success;
1598 brelse(bh);
1599 if (retval == -1) {
1600 bh = ERR_PTR(ERR_BAD_DX_DIR);
1601 goto errout;
1602 }
1603
1604 /* Check to see if we should continue to search */
1605 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame,
1606 frames, NULL);
1607 if (retval < 0) {
1608 ext4_warning_inode(dir,
1609 "error %d reading directory index block",
1610 retval);
1611 bh = ERR_PTR(retval);
1612 goto errout;
1613 }
1614 } while (retval == 1);
1615
1616 bh = NULL;
1617 errout:
1618 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name));
1619 success:
1620 dx_release(frames);
1621 return bh;
1622 }
1623
1624 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
1625 {
1626 struct inode *inode;
1627 struct ext4_dir_entry_2 *de;
1628 struct buffer_head *bh;
1629
1630 if (dentry->d_name.len > EXT4_NAME_LEN)
1631 return ERR_PTR(-ENAMETOOLONG);
1632
1633 bh = ext4_lookup_entry(dir, dentry, &de);
1634 if (IS_ERR(bh))
1635 return ERR_CAST(bh);
1636 inode = NULL;
1637 if (bh) {
1638 __u32 ino = le32_to_cpu(de->inode);
1639 brelse(bh);
1640 if (!ext4_valid_inum(dir->i_sb, ino)) {
1641 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1642 return ERR_PTR(-EFSCORRUPTED);
1643 }
1644 if (unlikely(ino == dir->i_ino)) {
1645 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
1646 dentry);
1647 return ERR_PTR(-EFSCORRUPTED);
1648 }
1649 inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL);
1650 if (inode == ERR_PTR(-ESTALE)) {
1651 EXT4_ERROR_INODE(dir,
1652 "deleted inode referenced: %u",
1653 ino);
1654 return ERR_PTR(-EFSCORRUPTED);
1655 }
1656 if (!IS_ERR(inode) && IS_ENCRYPTED(dir) &&
1657 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
1658 !fscrypt_has_permitted_context(dir, inode)) {
1659 ext4_warning(inode->i_sb,
1660 "Inconsistent encryption contexts: %lu/%lu",
1661 dir->i_ino, inode->i_ino);
1662 iput(inode);
1663 return ERR_PTR(-EPERM);
1664 }
1665 }
1666
1667 #ifdef CONFIG_UNICODE
1668 if (!inode && IS_CASEFOLDED(dir)) {
1669 /* Eventually we want to call d_add_ci(dentry, NULL)
1670 * for negative dentries in the encoding case as
1671 * well. For now, prevent the negative dentry
1672 * from being cached.
1673 */
1674 return NULL;
1675 }
1676 #endif
1677 return d_splice_alias(inode, dentry);
1678 }
1679
1680
1681 struct dentry *ext4_get_parent(struct dentry *child)
1682 {
1683 __u32 ino;
1684 static const struct qstr dotdot = QSTR_INIT("..", 2);
1685 struct ext4_dir_entry_2 * de;
1686 struct buffer_head *bh;
1687
1688 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL);
1689 if (IS_ERR(bh))
1690 return ERR_CAST(bh);
1691 if (!bh)
1692 return ERR_PTR(-ENOENT);
1693 ino = le32_to_cpu(de->inode);
1694 brelse(bh);
1695
1696 if (!ext4_valid_inum(child->d_sb, ino)) {
1697 EXT4_ERROR_INODE(d_inode(child),
1698 "bad parent inode number: %u", ino);
1699 return ERR_PTR(-EFSCORRUPTED);
1700 }
1701
1702 return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL));
1703 }
1704
1705 /*
1706 * Move count entries from end of map between two memory locations.
1707 * Returns pointer to last entry moved.
1708 */
1709 static struct ext4_dir_entry_2 *
1710 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1711 unsigned blocksize)
1712 {
1713 unsigned rec_len = 0;
1714
1715 while (count--) {
1716 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
1717 (from + (map->offs<<2));
1718 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1719 memcpy (to, de, rec_len);
1720 ((struct ext4_dir_entry_2 *) to)->rec_len =
1721 ext4_rec_len_to_disk(rec_len, blocksize);
1722 de->inode = 0;
1723 map++;
1724 to += rec_len;
1725 }
1726 return (struct ext4_dir_entry_2 *) (to - rec_len);
1727 }
1728
1729 /*
1730 * Compact each dir entry in the range to the minimal rec_len.
1731 * Returns pointer to last entry in range.
1732 */
1733 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
1734 {
1735 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
1736 unsigned rec_len = 0;
1737
1738 prev = to = de;
1739 while ((char*)de < base + blocksize) {
1740 next = ext4_next_entry(de, blocksize);
1741 if (de->inode && de->name_len) {
1742 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1743 if (de > to)
1744 memmove(to, de, rec_len);
1745 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
1746 prev = to;
1747 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
1748 }
1749 de = next;
1750 }
1751 return prev;
1752 }
1753
1754 /*
1755 * Split a full leaf block to make room for a new dir entry.
1756 * Allocate a new block, and move entries so that they are approx. equally full.
1757 * Returns pointer to de in block into which the new entry will be inserted.
1758 */
1759 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1760 struct buffer_head **bh,struct dx_frame *frame,
1761 struct dx_hash_info *hinfo)
1762 {
1763 unsigned blocksize = dir->i_sb->s_blocksize;
1764 unsigned count, continued;
1765 struct buffer_head *bh2;
1766 ext4_lblk_t newblock;
1767 u32 hash2;
1768 struct dx_map_entry *map;
1769 char *data1 = (*bh)->b_data, *data2;
1770 unsigned split, move, size;
1771 struct ext4_dir_entry_2 *de = NULL, *de2;
1772 struct ext4_dir_entry_tail *t;
1773 int csum_size = 0;
1774 int err = 0, i;
1775
1776 if (ext4_has_metadata_csum(dir->i_sb))
1777 csum_size = sizeof(struct ext4_dir_entry_tail);
1778
1779 bh2 = ext4_append(handle, dir, &newblock);
1780 if (IS_ERR(bh2)) {
1781 brelse(*bh);
1782 *bh = NULL;
1783 return (struct ext4_dir_entry_2 *) bh2;
1784 }
1785
1786 BUFFER_TRACE(*bh, "get_write_access");
1787 err = ext4_journal_get_write_access(handle, *bh);
1788 if (err)
1789 goto journal_error;
1790
1791 BUFFER_TRACE(frame->bh, "get_write_access");
1792 err = ext4_journal_get_write_access(handle, frame->bh);
1793 if (err)
1794 goto journal_error;
1795
1796 data2 = bh2->b_data;
1797
1798 /* create map in the end of data2 block */
1799 map = (struct dx_map_entry *) (data2 + blocksize);
1800 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1,
1801 blocksize, hinfo, map);
1802 map -= count;
1803 dx_sort_map(map, count);
1804 /* Split the existing block in the middle, size-wise */
1805 size = 0;
1806 move = 0;
1807 for (i = count-1; i >= 0; i--) {
1808 /* is more than half of this entry in 2nd half of the block? */
1809 if (size + map[i].size/2 > blocksize/2)
1810 break;
1811 size += map[i].size;
1812 move++;
1813 }
1814 /* map index at which we will split */
1815 split = count - move;
1816 hash2 = map[split].hash;
1817 continued = hash2 == map[split - 1].hash;
1818 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1819 (unsigned long)dx_get_block(frame->at),
1820 hash2, split, count-split));
1821
1822 /* Fancy dance to stay within two buffers */
1823 de2 = dx_move_dirents(data1, data2, map + split, count - split,
1824 blocksize);
1825 de = dx_pack_dirents(data1, blocksize);
1826 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1827 (char *) de,
1828 blocksize);
1829 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1830 (char *) de2,
1831 blocksize);
1832 if (csum_size) {
1833 t = EXT4_DIRENT_TAIL(data2, blocksize);
1834 initialize_dirent_tail(t, blocksize);
1835
1836 t = EXT4_DIRENT_TAIL(data1, blocksize);
1837 initialize_dirent_tail(t, blocksize);
1838 }
1839
1840 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
1841 blocksize, 1));
1842 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,
1843 blocksize, 1));
1844
1845 /* Which block gets the new entry? */
1846 if (hinfo->hash >= hash2) {
1847 swap(*bh, bh2);
1848 de = de2;
1849 }
1850 dx_insert_block(frame, hash2 + continued, newblock);
1851 err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
1852 if (err)
1853 goto journal_error;
1854 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1855 if (err)
1856 goto journal_error;
1857 brelse(bh2);
1858 dxtrace(dx_show_index("frame", frame->entries));
1859 return de;
1860
1861 journal_error:
1862 brelse(*bh);
1863 brelse(bh2);
1864 *bh = NULL;
1865 ext4_std_error(dir->i_sb, err);
1866 return ERR_PTR(err);
1867 }
1868
1869 int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1870 struct buffer_head *bh,
1871 void *buf, int buf_size,
1872 struct ext4_filename *fname,
1873 struct ext4_dir_entry_2 **dest_de)
1874 {
1875 struct ext4_dir_entry_2 *de;
1876 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname));
1877 int nlen, rlen;
1878 unsigned int offset = 0;
1879 char *top;
1880
1881 de = (struct ext4_dir_entry_2 *)buf;
1882 top = buf + buf_size - reclen;
1883 while ((char *) de <= top) {
1884 if (ext4_check_dir_entry(dir, NULL, de, bh,
1885 buf, buf_size, offset))
1886 return -EFSCORRUPTED;
1887 if (ext4_match(dir, fname, de))
1888 return -EEXIST;
1889 nlen = EXT4_DIR_REC_LEN(de->name_len);
1890 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1891 if ((de->inode ? rlen - nlen : rlen) >= reclen)
1892 break;
1893 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1894 offset += rlen;
1895 }
1896 if ((char *) de > top)
1897 return -ENOSPC;
1898
1899 *dest_de = de;
1900 return 0;
1901 }
1902
1903 void ext4_insert_dentry(struct inode *inode,
1904 struct ext4_dir_entry_2 *de,
1905 int buf_size,
1906 struct ext4_filename *fname)
1907 {
1908
1909 int nlen, rlen;
1910
1911 nlen = EXT4_DIR_REC_LEN(de->name_len);
1912 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1913 if (de->inode) {
1914 struct ext4_dir_entry_2 *de1 =
1915 (struct ext4_dir_entry_2 *)((char *)de + nlen);
1916 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
1917 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
1918 de = de1;
1919 }
1920 de->file_type = EXT4_FT_UNKNOWN;
1921 de->inode = cpu_to_le32(inode->i_ino);
1922 ext4_set_de_type(inode->i_sb, de, inode->i_mode);
1923 de->name_len = fname_len(fname);
1924 memcpy(de->name, fname_name(fname), fname_len(fname));
1925 }
1926
1927 /*
1928 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1929 * it points to a directory entry which is guaranteed to be large
1930 * enough for new directory entry. If de is NULL, then
1931 * add_dirent_to_buf will attempt search the directory block for
1932 * space. It will return -ENOSPC if no space is available, and -EIO
1933 * and -EEXIST if directory entry already exists.
1934 */
1935 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
1936 struct inode *dir,
1937 struct inode *inode, struct ext4_dir_entry_2 *de,
1938 struct buffer_head *bh)
1939 {
1940 unsigned int blocksize = dir->i_sb->s_blocksize;
1941 int csum_size = 0;
1942 int err;
1943
1944 if (ext4_has_metadata_csum(inode->i_sb))
1945 csum_size = sizeof(struct ext4_dir_entry_tail);
1946
1947 if (!de) {
1948 err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
1949 blocksize - csum_size, fname, &de);
1950 if (err)
1951 return err;
1952 }
1953 BUFFER_TRACE(bh, "get_write_access");
1954 err = ext4_journal_get_write_access(handle, bh);
1955 if (err) {
1956 ext4_std_error(dir->i_sb, err);
1957 return err;
1958 }
1959
1960 /* By now the buffer is marked for journaling */
1961 ext4_insert_dentry(inode, de, blocksize, fname);
1962
1963 /*
1964 * XXX shouldn't update any times until successful
1965 * completion of syscall, but too many callers depend
1966 * on this.
1967 *
1968 * XXX similarly, too many callers depend on
1969 * ext4_new_inode() setting the times, but error
1970 * recovery deletes the inode, so the worst that can
1971 * happen is that the times are slightly out of date
1972 * and/or different from the directory change time.
1973 */
1974 dir->i_mtime = dir->i_ctime = current_time(dir);
1975 ext4_update_dx_flag(dir);
1976 inode_inc_iversion(dir);
1977 ext4_mark_inode_dirty(handle, dir);
1978 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
1979 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
1980 if (err)
1981 ext4_std_error(dir->i_sb, err);
1982 return 0;
1983 }
1984
1985 /*
1986 * This converts a one block unindexed directory to a 3 block indexed
1987 * directory, and adds the dentry to the indexed directory.
1988 */
1989 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
1990 struct inode *dir,
1991 struct inode *inode, struct buffer_head *bh)
1992 {
1993 struct buffer_head *bh2;
1994 struct dx_root *root;
1995 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1996 struct dx_entry *entries;
1997 struct ext4_dir_entry_2 *de, *de2;
1998 struct ext4_dir_entry_tail *t;
1999 char *data1, *top;
2000 unsigned len;
2001 int retval;
2002 unsigned blocksize;
2003 ext4_lblk_t block;
2004 struct fake_dirent *fde;
2005 int csum_size = 0;
2006
2007 if (ext4_has_metadata_csum(inode->i_sb))
2008 csum_size = sizeof(struct ext4_dir_entry_tail);
2009
2010 blocksize = dir->i_sb->s_blocksize;
2011 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
2012 BUFFER_TRACE(bh, "get_write_access");
2013 retval = ext4_journal_get_write_access(handle, bh);
2014 if (retval) {
2015 ext4_std_error(dir->i_sb, retval);
2016 brelse(bh);
2017 return retval;
2018 }
2019 root = (struct dx_root *) bh->b_data;
2020
2021 /* The 0th block becomes the root, move the dirents out */
2022 fde = &root->dotdot;
2023 de = (struct ext4_dir_entry_2 *)((char *)fde +
2024 ext4_rec_len_from_disk(fde->rec_len, blocksize));
2025 if ((char *) de >= (((char *) root) + blocksize)) {
2026 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
2027 brelse(bh);
2028 return -EFSCORRUPTED;
2029 }
2030 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
2031
2032 /* Allocate new block for the 0th block's dirents */
2033 bh2 = ext4_append(handle, dir, &block);
2034 if (IS_ERR(bh2)) {
2035 brelse(bh);
2036 return PTR_ERR(bh2);
2037 }
2038 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
2039 data1 = bh2->b_data;
2040
2041 memcpy (data1, de, len);
2042 de = (struct ext4_dir_entry_2 *) data1;
2043 top = data1 + len;
2044 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
2045 de = de2;
2046 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
2047 (char *) de,
2048 blocksize);
2049
2050 if (csum_size) {
2051 t = EXT4_DIRENT_TAIL(data1, blocksize);
2052 initialize_dirent_tail(t, blocksize);
2053 }
2054
2055 /* Initialize the root; the dot dirents already exist */
2056 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
2057 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
2058 blocksize);
2059 memset (&root->info, 0, sizeof(root->info));
2060 root->info.info_length = sizeof(root->info);
2061 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
2062 entries = root->entries;
2063 dx_set_block(entries, 1);
2064 dx_set_count(entries, 1);
2065 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
2066
2067 /* Initialize as for dx_probe */
2068 fname->hinfo.hash_version = root->info.hash_version;
2069 if (fname->hinfo.hash_version <= DX_HASH_TEA)
2070 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
2071 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
2072 ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), &fname->hinfo);
2073
2074 memset(frames, 0, sizeof(frames));
2075 frame = frames;
2076 frame->entries = entries;
2077 frame->at = entries;
2078 frame->bh = bh;
2079
2080 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
2081 if (retval)
2082 goto out_frames;
2083 retval = ext4_handle_dirty_dirent_node(handle, dir, bh2);
2084 if (retval)
2085 goto out_frames;
2086
2087 de = do_split(handle,dir, &bh2, frame, &fname->hinfo);
2088 if (IS_ERR(de)) {
2089 retval = PTR_ERR(de);
2090 goto out_frames;
2091 }
2092
2093 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2);
2094 out_frames:
2095 /*
2096 * Even if the block split failed, we have to properly write
2097 * out all the changes we did so far. Otherwise we can end up
2098 * with corrupted filesystem.
2099 */
2100 if (retval)
2101 ext4_mark_inode_dirty(handle, dir);
2102 dx_release(frames);
2103 brelse(bh2);
2104 return retval;
2105 }
2106
2107 /*
2108 * ext4_add_entry()
2109 *
2110 * adds a file entry to the specified directory, using the same
2111 * semantics as ext4_find_entry(). It returns NULL if it failed.
2112 *
2113 * NOTE!! The inode part of 'de' is left at 0 - which means you
2114 * may not sleep between calling this and putting something into
2115 * the entry, as someone else might have used it while you slept.
2116 */
2117 static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
2118 struct inode *inode)
2119 {
2120 struct inode *dir = d_inode(dentry->d_parent);
2121 struct buffer_head *bh = NULL;
2122 struct ext4_dir_entry_2 *de;
2123 struct ext4_dir_entry_tail *t;
2124 struct super_block *sb;
2125 struct ext4_sb_info *sbi;
2126 struct ext4_filename fname;
2127 int retval;
2128 int dx_fallback=0;
2129 unsigned blocksize;
2130 ext4_lblk_t block, blocks;
2131 int csum_size = 0;
2132
2133 if (ext4_has_metadata_csum(inode->i_sb))
2134 csum_size = sizeof(struct ext4_dir_entry_tail);
2135
2136 sb = dir->i_sb;
2137 sbi = EXT4_SB(sb);
2138 blocksize = sb->s_blocksize;
2139 if (!dentry->d_name.len)
2140 return -EINVAL;
2141
2142 #ifdef CONFIG_UNICODE
2143 if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) &&
2144 utf8_validate(sbi->s_encoding, &dentry->d_name))
2145 return -EINVAL;
2146 #endif
2147
2148 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);
2149 if (retval)
2150 return retval;
2151
2152 if (ext4_has_inline_data(dir)) {
2153 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode);
2154 if (retval < 0)
2155 goto out;
2156 if (retval == 1) {
2157 retval = 0;
2158 goto out;
2159 }
2160 }
2161
2162 if (is_dx(dir)) {
2163 retval = ext4_dx_add_entry(handle, &fname, dir, inode);
2164 if (!retval || (retval != ERR_BAD_DX_DIR))
2165 goto out;
2166 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
2167 dx_fallback++;
2168 ext4_mark_inode_dirty(handle, dir);
2169 }
2170 blocks = dir->i_size >> sb->s_blocksize_bits;
2171 for (block = 0; block < blocks; block++) {
2172 bh = ext4_read_dirblock(dir, block, DIRENT);
2173 if (IS_ERR(bh)) {
2174 retval = PTR_ERR(bh);
2175 bh = NULL;
2176 goto out;
2177 }
2178 retval = add_dirent_to_buf(handle, &fname, dir, inode,
2179 NULL, bh);
2180 if (retval != -ENOSPC)
2181 goto out;
2182
2183 if (blocks == 1 && !dx_fallback &&
2184 ext4_has_feature_dir_index(sb)) {
2185 retval = make_indexed_dir(handle, &fname, dir,
2186 inode, bh);
2187 bh = NULL; /* make_indexed_dir releases bh */
2188 goto out;
2189 }
2190 brelse(bh);
2191 }
2192 bh = ext4_append(handle, dir, &block);
2193 if (IS_ERR(bh)) {
2194 retval = PTR_ERR(bh);
2195 bh = NULL;
2196 goto out;
2197 }
2198 de = (struct ext4_dir_entry_2 *) bh->b_data;
2199 de->inode = 0;
2200 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
2201
2202 if (csum_size) {
2203 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
2204 initialize_dirent_tail(t, blocksize);
2205 }
2206
2207 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);
2208 out:
2209 ext4_fname_free_filename(&fname);
2210 brelse(bh);
2211 if (retval == 0)
2212 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
2213 return retval;
2214 }
2215
2216 /*
2217 * Returns 0 for success, or a negative error value
2218 */
2219 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
2220 struct inode *dir, struct inode *inode)
2221 {
2222 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2223 struct dx_entry *entries, *at;
2224 struct buffer_head *bh;
2225 struct super_block *sb = dir->i_sb;
2226 struct ext4_dir_entry_2 *de;
2227 int restart;
2228 int err;
2229
2230 again:
2231 restart = 0;
2232 frame = dx_probe(fname, dir, NULL, frames);
2233 if (IS_ERR(frame))
2234 return PTR_ERR(frame);
2235 entries = frame->entries;
2236 at = frame->at;
2237 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT);
2238 if (IS_ERR(bh)) {
2239 err = PTR_ERR(bh);
2240 bh = NULL;
2241 goto cleanup;
2242 }
2243
2244 BUFFER_TRACE(bh, "get_write_access");
2245 err = ext4_journal_get_write_access(handle, bh);
2246 if (err)
2247 goto journal_error;
2248
2249 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh);
2250 if (err != -ENOSPC)
2251 goto cleanup;
2252
2253 err = 0;
2254 /* Block full, should compress but for now just split */
2255 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
2256 dx_get_count(entries), dx_get_limit(entries)));
2257 /* Need to split index? */
2258 if (dx_get_count(entries) == dx_get_limit(entries)) {
2259 ext4_lblk_t newblock;
2260 int levels = frame - frames + 1;
2261 unsigned int icount;
2262 int add_level = 1;
2263 struct dx_entry *entries2;
2264 struct dx_node *node2;
2265 struct buffer_head *bh2;
2266
2267 while (frame > frames) {
2268 if (dx_get_count((frame - 1)->entries) <
2269 dx_get_limit((frame - 1)->entries)) {
2270 add_level = 0;
2271 break;
2272 }
2273 frame--; /* split higher index block */
2274 at = frame->at;
2275 entries = frame->entries;
2276 restart = 1;
2277 }
2278 if (add_level && levels == ext4_dir_htree_level(sb)) {
2279 ext4_warning(sb, "Directory (ino: %lu) index full, "
2280 "reach max htree level :%d",
2281 dir->i_ino, levels);
2282 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) {
2283 ext4_warning(sb, "Large directory feature is "
2284 "not enabled on this "
2285 "filesystem");
2286 }
2287 err = -ENOSPC;
2288 goto cleanup;
2289 }
2290 icount = dx_get_count(entries);
2291 bh2 = ext4_append(handle, dir, &newblock);
2292 if (IS_ERR(bh2)) {
2293 err = PTR_ERR(bh2);
2294 goto cleanup;
2295 }
2296 node2 = (struct dx_node *)(bh2->b_data);
2297 entries2 = node2->entries;
2298 memset(&node2->fake, 0, sizeof(struct fake_dirent));
2299 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
2300 sb->s_blocksize);
2301 BUFFER_TRACE(frame->bh, "get_write_access");
2302 err = ext4_journal_get_write_access(handle, frame->bh);
2303 if (err)
2304 goto journal_error;
2305 if (!add_level) {
2306 unsigned icount1 = icount/2, icount2 = icount - icount1;
2307 unsigned hash2 = dx_get_hash(entries + icount1);
2308 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2309 icount1, icount2));
2310
2311 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
2312 err = ext4_journal_get_write_access(handle,
2313 (frame - 1)->bh);
2314 if (err)
2315 goto journal_error;
2316
2317 memcpy((char *) entries2, (char *) (entries + icount1),
2318 icount2 * sizeof(struct dx_entry));
2319 dx_set_count(entries, icount1);
2320 dx_set_count(entries2, icount2);
2321 dx_set_limit(entries2, dx_node_limit(dir));
2322
2323 /* Which index block gets the new entry? */
2324 if (at - entries >= icount1) {
2325 frame->at = at = at - entries - icount1 + entries2;
2326 frame->entries = entries = entries2;
2327 swap(frame->bh, bh2);
2328 }
2329 dx_insert_block((frame - 1), hash2, newblock);
2330 dxtrace(dx_show_index("node", frame->entries));
2331 dxtrace(dx_show_index("node",
2332 ((struct dx_node *) bh2->b_data)->entries));
2333 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2334 if (err)
2335 goto journal_error;
2336 brelse (bh2);
2337 err = ext4_handle_dirty_dx_node(handle, dir,
2338 (frame - 1)->bh);
2339 if (err)
2340 goto journal_error;
2341 if (restart) {
2342 err = ext4_handle_dirty_dx_node(handle, dir,
2343 frame->bh);
2344 goto journal_error;
2345 }
2346 } else {
2347 struct dx_root *dxroot;
2348 memcpy((char *) entries2, (char *) entries,
2349 icount * sizeof(struct dx_entry));
2350 dx_set_limit(entries2, dx_node_limit(dir));
2351
2352 /* Set up root */
2353 dx_set_count(entries, 1);
2354 dx_set_block(entries + 0, newblock);
2355 dxroot = (struct dx_root *)frames[0].bh->b_data;
2356 dxroot->info.indirect_levels += 1;
2357 dxtrace(printk(KERN_DEBUG
2358 "Creating %d level index...\n",
2359 dxroot->info.indirect_levels));
2360 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
2361 if (err)
2362 goto journal_error;
2363 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2364 brelse(bh2);
2365 restart = 1;
2366 goto journal_error;
2367 }
2368 }
2369 de = do_split(handle, dir, &bh, frame, &fname->hinfo);
2370 if (IS_ERR(de)) {
2371 err = PTR_ERR(de);
2372 goto cleanup;
2373 }
2374 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh);
2375 goto cleanup;
2376
2377 journal_error:
2378 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */
2379 cleanup:
2380 brelse(bh);
2381 dx_release(frames);
2382 /* @restart is true means htree-path has been changed, we need to
2383 * repeat dx_probe() to find out valid htree-path
2384 */
2385 if (restart && err == 0)
2386 goto again;
2387 return err;
2388 }
2389
2390 /*
2391 * ext4_generic_delete_entry deletes a directory entry by merging it
2392 * with the previous entry
2393 */
2394 int ext4_generic_delete_entry(handle_t *handle,
2395 struct inode *dir,
2396 struct ext4_dir_entry_2 *de_del,
2397 struct buffer_head *bh,
2398 void *entry_buf,
2399 int buf_size,
2400 int csum_size)
2401 {
2402 struct ext4_dir_entry_2 *de, *pde;
2403 unsigned int blocksize = dir->i_sb->s_blocksize;
2404 int i;
2405
2406 i = 0;
2407 pde = NULL;
2408 de = (struct ext4_dir_entry_2 *)entry_buf;
2409 while (i < buf_size - csum_size) {
2410 if (ext4_check_dir_entry(dir, NULL, de, bh,
2411 bh->b_data, bh->b_size, i))
2412 return -EFSCORRUPTED;
2413 if (de == de_del) {
2414 if (pde)
2415 pde->rec_len = ext4_rec_len_to_disk(
2416 ext4_rec_len_from_disk(pde->rec_len,
2417 blocksize) +
2418 ext4_rec_len_from_disk(de->rec_len,
2419 blocksize),
2420 blocksize);
2421 else
2422 de->inode = 0;
2423 inode_inc_iversion(dir);
2424 return 0;
2425 }
2426 i += ext4_rec_len_from_disk(de->rec_len, blocksize);
2427 pde = de;
2428 de = ext4_next_entry(de, blocksize);
2429 }
2430 return -ENOENT;
2431 }
2432
2433 static int ext4_delete_entry(handle_t *handle,
2434 struct inode *dir,
2435 struct ext4_dir_entry_2 *de_del,
2436 struct buffer_head *bh)
2437 {
2438 int err, csum_size = 0;
2439
2440 if (ext4_has_inline_data(dir)) {
2441 int has_inline_data = 1;
2442 err = ext4_delete_inline_entry(handle, dir, de_del, bh,
2443 &has_inline_data);
2444 if (has_inline_data)
2445 return err;
2446 }
2447
2448 if (ext4_has_metadata_csum(dir->i_sb))
2449 csum_size = sizeof(struct ext4_dir_entry_tail);
2450
2451 BUFFER_TRACE(bh, "get_write_access");
2452 err = ext4_journal_get_write_access(handle, bh);
2453 if (unlikely(err))
2454 goto out;
2455
2456 err = ext4_generic_delete_entry(handle, dir, de_del,
2457 bh, bh->b_data,
2458 dir->i_sb->s_blocksize, csum_size);
2459 if (err)
2460 goto out;
2461
2462 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2463 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
2464 if (unlikely(err))
2465 goto out;
2466
2467 return 0;
2468 out:
2469 if (err != -ENOENT)
2470 ext4_std_error(dir->i_sb, err);
2471 return err;
2472 }
2473
2474 /*
2475 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2
2476 * since this indicates that nlinks count was previously 1 to avoid overflowing
2477 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean
2478 * that subdirectory link counts are not being maintained accurately.
2479 *
2480 * The caller has already checked for i_nlink overflow in case the DIR_LINK
2481 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy
2482 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set
2483 * on regular files) and to avoid creating huge/slow non-HTREE directories.
2484 */
2485 static void ext4_inc_count(handle_t *handle, struct inode *inode)
2486 {
2487 inc_nlink(inode);
2488 if (is_dx(inode) &&
2489 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))
2490 set_nlink(inode, 1);
2491 }
2492
2493 /*
2494 * If a directory had nlink == 1, then we should let it be 1. This indicates
2495 * directory has >EXT4_LINK_MAX subdirs.
2496 */
2497 static void ext4_dec_count(handle_t *handle, struct inode *inode)
2498 {
2499 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2500 drop_nlink(inode);
2501 }
2502
2503
2504 static int ext4_add_nondir(handle_t *handle,
2505 struct dentry *dentry, struct inode *inode)
2506 {
2507 int err = ext4_add_entry(handle, dentry, inode);
2508 if (!err) {
2509 ext4_mark_inode_dirty(handle, inode);
2510 d_instantiate_new(dentry, inode);
2511 return 0;
2512 }
2513 drop_nlink(inode);
2514 unlock_new_inode(inode);
2515 iput(inode);
2516 return err;
2517 }
2518
2519 /*
2520 * By the time this is called, we already have created
2521 * the directory cache entry for the new file, but it
2522 * is so far negative - it has no inode.
2523 *
2524 * If the create succeeds, we fill in the inode information
2525 * with d_instantiate().
2526 */
2527 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
2528 bool excl)
2529 {
2530 handle_t *handle;
2531 struct inode *inode;
2532 int err, credits, retries = 0;
2533
2534 err = dquot_initialize(dir);
2535 if (err)
2536 return err;
2537
2538 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2539 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2540 retry:
2541 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2542 NULL, EXT4_HT_DIR, credits);
2543 handle = ext4_journal_current_handle();
2544 err = PTR_ERR(inode);
2545 if (!IS_ERR(inode)) {
2546 inode->i_op = &ext4_file_inode_operations;
2547 inode->i_fop = &ext4_file_operations;
2548 ext4_set_aops(inode);
2549 err = ext4_add_nondir(handle, dentry, inode);
2550 if (!err && IS_DIRSYNC(dir))
2551 ext4_handle_sync(handle);
2552 }
2553 if (handle)
2554 ext4_journal_stop(handle);
2555 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2556 goto retry;
2557 return err;
2558 }
2559
2560 static int ext4_mknod(struct inode *dir, struct dentry *dentry,
2561 umode_t mode, dev_t rdev)
2562 {
2563 handle_t *handle;
2564 struct inode *inode;
2565 int err, credits, retries = 0;
2566
2567 err = dquot_initialize(dir);
2568 if (err)
2569 return err;
2570
2571 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2572 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2573 retry:
2574 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2575 NULL, EXT4_HT_DIR, credits);
2576 handle = ext4_journal_current_handle();
2577 err = PTR_ERR(inode);
2578 if (!IS_ERR(inode)) {
2579 init_special_inode(inode, inode->i_mode, rdev);
2580 inode->i_op = &ext4_special_inode_operations;
2581 err = ext4_add_nondir(handle, dentry, inode);
2582 if (!err && IS_DIRSYNC(dir))
2583 ext4_handle_sync(handle);
2584 }
2585 if (handle)
2586 ext4_journal_stop(handle);
2587 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2588 goto retry;
2589 return err;
2590 }
2591
2592 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
2593 {
2594 handle_t *handle;
2595 struct inode *inode;
2596 int err, retries = 0;
2597
2598 err = dquot_initialize(dir);
2599 if (err)
2600 return err;
2601
2602 retry:
2603 inode = ext4_new_inode_start_handle(dir, mode,
2604 NULL, 0, NULL,
2605 EXT4_HT_DIR,
2606 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2607 4 + EXT4_XATTR_TRANS_BLOCKS);
2608 handle = ext4_journal_current_handle();
2609 err = PTR_ERR(inode);
2610 if (!IS_ERR(inode)) {
2611 inode->i_op = &ext4_file_inode_operations;
2612 inode->i_fop = &ext4_file_operations;
2613 ext4_set_aops(inode);
2614 d_tmpfile(dentry, inode);
2615 err = ext4_orphan_add(handle, inode);
2616 if (err)
2617 goto err_unlock_inode;
2618 mark_inode_dirty(inode);
2619 unlock_new_inode(inode);
2620 }
2621 if (handle)
2622 ext4_journal_stop(handle);
2623 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2624 goto retry;
2625 return err;
2626 err_unlock_inode:
2627 ext4_journal_stop(handle);
2628 unlock_new_inode(inode);
2629 return err;
2630 }
2631
2632 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2633 struct ext4_dir_entry_2 *de,
2634 int blocksize, int csum_size,
2635 unsigned int parent_ino, int dotdot_real_len)
2636 {
2637 de->inode = cpu_to_le32(inode->i_ino);
2638 de->name_len = 1;
2639 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2640 blocksize);
2641 strcpy(de->name, ".");
2642 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2643
2644 de = ext4_next_entry(de, blocksize);
2645 de->inode = cpu_to_le32(parent_ino);
2646 de->name_len = 2;
2647 if (!dotdot_real_len)
2648 de->rec_len = ext4_rec_len_to_disk(blocksize -
2649 (csum_size + EXT4_DIR_REC_LEN(1)),
2650 blocksize);
2651 else
2652 de->rec_len = ext4_rec_len_to_disk(
2653 EXT4_DIR_REC_LEN(de->name_len), blocksize);
2654 strcpy(de->name, "..");
2655 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2656
2657 return ext4_next_entry(de, blocksize);
2658 }
2659
2660 static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2661 struct inode *inode)
2662 {
2663 struct buffer_head *dir_block = NULL;
2664 struct ext4_dir_entry_2 *de;
2665 struct ext4_dir_entry_tail *t;
2666 ext4_lblk_t block = 0;
2667 unsigned int blocksize = dir->i_sb->s_blocksize;
2668 int csum_size = 0;
2669 int err;
2670
2671 if (ext4_has_metadata_csum(dir->i_sb))
2672 csum_size = sizeof(struct ext4_dir_entry_tail);
2673
2674 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
2675 err = ext4_try_create_inline_dir(handle, dir, inode);
2676 if (err < 0 && err != -ENOSPC)
2677 goto out;
2678 if (!err)
2679 goto out;
2680 }
2681
2682 inode->i_size = 0;
2683 dir_block = ext4_append(handle, inode, &block);
2684 if (IS_ERR(dir_block))
2685 return PTR_ERR(dir_block);
2686 de = (struct ext4_dir_entry_2 *)dir_block->b_data;
2687 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
2688 set_nlink(inode, 2);
2689 if (csum_size) {
2690 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
2691 initialize_dirent_tail(t, blocksize);
2692 }
2693
2694 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2695 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
2696 if (err)
2697 goto out;
2698 set_buffer_verified(dir_block);
2699 out:
2700 brelse(dir_block);
2701 return err;
2702 }
2703
2704 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2705 {
2706 handle_t *handle;
2707 struct inode *inode;
2708 int err, credits, retries = 0;
2709
2710 if (EXT4_DIR_LINK_MAX(dir))
2711 return -EMLINK;
2712
2713 err = dquot_initialize(dir);
2714 if (err)
2715 return err;
2716
2717 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2718 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2719 retry:
2720 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
2721 &dentry->d_name,
2722 0, NULL, EXT4_HT_DIR, credits);
2723 handle = ext4_journal_current_handle();
2724 err = PTR_ERR(inode);
2725 if (IS_ERR(inode))
2726 goto out_stop;
2727
2728 inode->i_op = &ext4_dir_inode_operations;
2729 inode->i_fop = &ext4_dir_operations;
2730 err = ext4_init_new_dir(handle, dir, inode);
2731 if (err)
2732 goto out_clear_inode;
2733 err = ext4_mark_inode_dirty(handle, inode);
2734 if (!err)
2735 err = ext4_add_entry(handle, dentry, inode);
2736 if (err) {
2737 out_clear_inode:
2738 clear_nlink(inode);
2739 unlock_new_inode(inode);
2740 ext4_mark_inode_dirty(handle, inode);
2741 iput(inode);
2742 goto out_stop;
2743 }
2744 ext4_inc_count(handle, dir);
2745 ext4_update_dx_flag(dir);
2746 err = ext4_mark_inode_dirty(handle, dir);
2747 if (err)
2748 goto out_clear_inode;
2749 d_instantiate_new(dentry, inode);
2750 if (IS_DIRSYNC(dir))
2751 ext4_handle_sync(handle);
2752
2753 out_stop:
2754 if (handle)
2755 ext4_journal_stop(handle);
2756 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2757 goto retry;
2758 return err;
2759 }
2760
2761 /*
2762 * routine to check that the specified directory is empty (for rmdir)
2763 */
2764 bool ext4_empty_dir(struct inode *inode)
2765 {
2766 unsigned int offset;
2767 struct buffer_head *bh;
2768 struct ext4_dir_entry_2 *de, *de1;
2769 struct super_block *sb;
2770
2771 if (ext4_has_inline_data(inode)) {
2772 int has_inline_data = 1;
2773 int ret;
2774
2775 ret = empty_inline_dir(inode, &has_inline_data);
2776 if (has_inline_data)
2777 return ret;
2778 }
2779
2780 sb = inode->i_sb;
2781 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
2782 EXT4_ERROR_INODE(inode, "invalid size");
2783 return true;
2784 }
2785 bh = ext4_read_dirblock(inode, 0, EITHER);
2786 if (IS_ERR(bh))
2787 return true;
2788
2789 de = (struct ext4_dir_entry_2 *) bh->b_data;
2790 de1 = ext4_next_entry(de, sb->s_blocksize);
2791 if (le32_to_cpu(de->inode) != inode->i_ino ||
2792 le32_to_cpu(de1->inode) == 0 ||
2793 strcmp(".", de->name) || strcmp("..", de1->name)) {
2794 ext4_warning_inode(inode, "directory missing '.' and/or '..'");
2795 brelse(bh);
2796 return true;
2797 }
2798 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
2799 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
2800 de = ext4_next_entry(de1, sb->s_blocksize);
2801 while (offset < inode->i_size) {
2802 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
2803 unsigned int lblock;
2804 brelse(bh);
2805 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
2806 bh = ext4_read_dirblock(inode, lblock, EITHER);
2807 if (IS_ERR(bh))
2808 return true;
2809 de = (struct ext4_dir_entry_2 *) bh->b_data;
2810 }
2811 if (ext4_check_dir_entry(inode, NULL, de, bh,
2812 bh->b_data, bh->b_size, offset)) {
2813 de = (struct ext4_dir_entry_2 *)(bh->b_data +
2814 sb->s_blocksize);
2815 offset = (offset | (sb->s_blocksize - 1)) + 1;
2816 continue;
2817 }
2818 if (le32_to_cpu(de->inode)) {
2819 brelse(bh);
2820 return false;
2821 }
2822 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2823 de = ext4_next_entry(de, sb->s_blocksize);
2824 }
2825 brelse(bh);
2826 return true;
2827 }
2828
2829 /*
2830 * ext4_orphan_add() links an unlinked or truncated inode into a list of
2831 * such inodes, starting at the superblock, in case we crash before the
2832 * file is closed/deleted, or in case the inode truncate spans multiple
2833 * transactions and the last transaction is not recovered after a crash.
2834 *
2835 * At filesystem recovery time, we walk this list deleting unlinked
2836 * inodes and truncating linked inodes in ext4_orphan_cleanup().
2837 *
2838 * Orphan list manipulation functions must be called under i_mutex unless
2839 * we are just creating the inode or deleting it.
2840 */
2841 int ext4_orphan_add(handle_t *handle, struct inode *inode)
2842 {
2843 struct super_block *sb = inode->i_sb;
2844 struct ext4_sb_info *sbi = EXT4_SB(sb);
2845 struct ext4_iloc iloc;
2846 int err = 0, rc;
2847 bool dirty = false;
2848
2849 if (!sbi->s_journal || is_bad_inode(inode))
2850 return 0;
2851
2852 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
2853 !inode_is_locked(inode));
2854 /*
2855 * Exit early if inode already is on orphan list. This is a big speedup
2856 * since we don't have to contend on the global s_orphan_lock.
2857 */
2858 if (!list_empty(&EXT4_I(inode)->i_orphan))
2859 return 0;
2860
2861 /*
2862 * Orphan handling is only valid for files with data blocks
2863 * being truncated, or files being unlinked. Note that we either
2864 * hold i_mutex, or the inode can not be referenced from outside,
2865 * so i_nlink should not be bumped due to race
2866 */
2867 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2868 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
2869
2870 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2871 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
2872 if (err)
2873 goto out;
2874
2875 err = ext4_reserve_inode_write(handle, inode, &iloc);
2876 if (err)
2877 goto out;
2878
2879 mutex_lock(&sbi->s_orphan_lock);
2880 /*
2881 * Due to previous errors inode may be already a part of on-disk
2882 * orphan list. If so skip on-disk list modification.
2883 */
2884 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
2885 (le32_to_cpu(sbi->s_es->s_inodes_count))) {
2886 /* Insert this inode at the head of the on-disk orphan list */
2887 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
2888 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2889 dirty = true;
2890 }
2891 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
2892 mutex_unlock(&sbi->s_orphan_lock);
2893
2894 if (dirty) {
2895 err = ext4_handle_dirty_super(handle, sb);
2896 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
2897 if (!err)
2898 err = rc;
2899 if (err) {
2900 /*
2901 * We have to remove inode from in-memory list if
2902 * addition to on disk orphan list failed. Stray orphan
2903 * list entries can cause panics at unmount time.
2904 */
2905 mutex_lock(&sbi->s_orphan_lock);
2906 list_del_init(&EXT4_I(inode)->i_orphan);
2907 mutex_unlock(&sbi->s_orphan_lock);
2908 }
2909 } else
2910 brelse(iloc.bh);
2911
2912 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
2913 jbd_debug(4, "orphan inode %lu will point to %d\n",
2914 inode->i_ino, NEXT_ORPHAN(inode));
2915 out:
2916 ext4_std_error(sb, err);
2917 return err;
2918 }
2919
2920 /*
2921 * ext4_orphan_del() removes an unlinked or truncated inode from the list
2922 * of such inodes stored on disk, because it is finally being cleaned up.
2923 */
2924 int ext4_orphan_del(handle_t *handle, struct inode *inode)
2925 {
2926 struct list_head *prev;
2927 struct ext4_inode_info *ei = EXT4_I(inode);
2928 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
2929 __u32 ino_next;
2930 struct ext4_iloc iloc;
2931 int err = 0;
2932
2933 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
2934 return 0;
2935
2936 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
2937 !inode_is_locked(inode));
2938 /* Do this quick check before taking global s_orphan_lock. */
2939 if (list_empty(&ei->i_orphan))
2940 return 0;
2941
2942 if (handle) {
2943 /* Grab inode buffer early before taking global s_orphan_lock */
2944 err = ext4_reserve_inode_write(handle, inode, &iloc);
2945 }
2946
2947 mutex_lock(&sbi->s_orphan_lock);
2948 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
2949
2950 prev = ei->i_orphan.prev;
2951 list_del_init(&ei->i_orphan);
2952
2953 /* If we're on an error path, we may not have a valid
2954 * transaction handle with which to update the orphan list on
2955 * disk, but we still need to remove the inode from the linked
2956 * list in memory. */
2957 if (!handle || err) {
2958 mutex_unlock(&sbi->s_orphan_lock);
2959 goto out_err;
2960 }
2961
2962 ino_next = NEXT_ORPHAN(inode);
2963 if (prev == &sbi->s_orphan) {
2964 jbd_debug(4, "superblock will point to %u\n", ino_next);
2965 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2966 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
2967 if (err) {
2968 mutex_unlock(&sbi->s_orphan_lock);
2969 goto out_brelse;
2970 }
2971 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
2972 mutex_unlock(&sbi->s_orphan_lock);
2973 err = ext4_handle_dirty_super(handle, inode->i_sb);
2974 } else {
2975 struct ext4_iloc iloc2;
2976 struct inode *i_prev =
2977 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
2978
2979 jbd_debug(4, "orphan inode %lu will point to %u\n",
2980 i_prev->i_ino, ino_next);
2981 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
2982 if (err) {
2983 mutex_unlock(&sbi->s_orphan_lock);
2984 goto out_brelse;
2985 }
2986 NEXT_ORPHAN(i_prev) = ino_next;
2987 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
2988 mutex_unlock(&sbi->s_orphan_lock);
2989 }
2990 if (err)
2991 goto out_brelse;
2992 NEXT_ORPHAN(inode) = 0;
2993 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
2994 out_err:
2995 ext4_std_error(inode->i_sb, err);
2996 return err;
2997
2998 out_brelse:
2999 brelse(iloc.bh);
3000 goto out_err;
3001 }
3002
3003 static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
3004 {
3005 int retval;
3006 struct inode *inode;
3007 struct buffer_head *bh;
3008 struct ext4_dir_entry_2 *de;
3009 handle_t *handle = NULL;
3010
3011 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3012 return -EIO;
3013
3014 /* Initialize quotas before so that eventual writes go in
3015 * separate transaction */
3016 retval = dquot_initialize(dir);
3017 if (retval)
3018 return retval;
3019 retval = dquot_initialize(d_inode(dentry));
3020 if (retval)
3021 return retval;
3022
3023 retval = -ENOENT;
3024 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
3025 if (IS_ERR(bh))
3026 return PTR_ERR(bh);
3027 if (!bh)
3028 goto end_rmdir;
3029
3030 inode = d_inode(dentry);
3031
3032 retval = -EFSCORRUPTED;
3033 if (le32_to_cpu(de->inode) != inode->i_ino)
3034 goto end_rmdir;
3035
3036 retval = -ENOTEMPTY;
3037 if (!ext4_empty_dir(inode))
3038 goto end_rmdir;
3039
3040 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3041 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3042 if (IS_ERR(handle)) {
3043 retval = PTR_ERR(handle);
3044 handle = NULL;
3045 goto end_rmdir;
3046 }
3047
3048 if (IS_DIRSYNC(dir))
3049 ext4_handle_sync(handle);
3050
3051 retval = ext4_delete_entry(handle, dir, de, bh);
3052 if (retval)
3053 goto end_rmdir;
3054 if (!EXT4_DIR_LINK_EMPTY(inode))
3055 ext4_warning_inode(inode,
3056 "empty directory '%.*s' has too many links (%u)",
3057 dentry->d_name.len, dentry->d_name.name,
3058 inode->i_nlink);
3059 inode_inc_iversion(inode);
3060 clear_nlink(inode);
3061 /* There's no need to set i_disksize: the fact that i_nlink is
3062 * zero will ensure that the right thing happens during any
3063 * recovery. */
3064 inode->i_size = 0;
3065 ext4_orphan_add(handle, inode);
3066 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode);
3067 ext4_mark_inode_dirty(handle, inode);
3068 ext4_dec_count(handle, dir);
3069 ext4_update_dx_flag(dir);
3070 ext4_mark_inode_dirty(handle, dir);
3071
3072 #ifdef CONFIG_UNICODE
3073 /* VFS negative dentries are incompatible with Encoding and
3074 * Case-insensitiveness. Eventually we'll want avoid
3075 * invalidating the dentries here, alongside with returning the
3076 * negative dentries at ext4_lookup(), when it is better
3077 * supported by the VFS for the CI case.
3078 */
3079 if (IS_CASEFOLDED(dir))
3080 d_invalidate(dentry);
3081 #endif
3082
3083 end_rmdir:
3084 brelse(bh);
3085 if (handle)
3086 ext4_journal_stop(handle);
3087 return retval;
3088 }
3089
3090 static int ext4_unlink(struct inode *dir, struct dentry *dentry)
3091 {
3092 int retval;
3093 struct inode *inode;
3094 struct buffer_head *bh;
3095 struct ext4_dir_entry_2 *de;
3096 handle_t *handle = NULL;
3097
3098 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3099 return -EIO;
3100
3101 trace_ext4_unlink_enter(dir, dentry);
3102 /* Initialize quotas before so that eventual writes go
3103 * in separate transaction */
3104 retval = dquot_initialize(dir);
3105 if (retval)
3106 return retval;
3107 retval = dquot_initialize(d_inode(dentry));
3108 if (retval)
3109 return retval;
3110
3111 retval = -ENOENT;
3112 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
3113 if (IS_ERR(bh))
3114 return PTR_ERR(bh);
3115 if (!bh)
3116 goto end_unlink;
3117
3118 inode = d_inode(dentry);
3119
3120 retval = -EFSCORRUPTED;
3121 if (le32_to_cpu(de->inode) != inode->i_ino)
3122 goto end_unlink;
3123
3124 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3125 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3126 if (IS_ERR(handle)) {
3127 retval = PTR_ERR(handle);
3128 handle = NULL;
3129 goto end_unlink;
3130 }
3131
3132 if (IS_DIRSYNC(dir))
3133 ext4_handle_sync(handle);
3134
3135 if (inode->i_nlink == 0) {
3136 ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
3137 dentry->d_name.len, dentry->d_name.name);
3138 set_nlink(inode, 1);
3139 }
3140 retval = ext4_delete_entry(handle, dir, de, bh);
3141 if (retval)
3142 goto end_unlink;
3143 dir->i_ctime = dir->i_mtime = current_time(dir);
3144 ext4_update_dx_flag(dir);
3145 ext4_mark_inode_dirty(handle, dir);
3146 drop_nlink(inode);
3147 if (!inode->i_nlink)
3148 ext4_orphan_add(handle, inode);
3149 inode->i_ctime = current_time(inode);
3150 ext4_mark_inode_dirty(handle, inode);
3151
3152 #ifdef CONFIG_UNICODE
3153 /* VFS negative dentries are incompatible with Encoding and
3154 * Case-insensitiveness. Eventually we'll want avoid
3155 * invalidating the dentries here, alongside with returning the
3156 * negative dentries at ext4_lookup(), when it is better
3157 * supported by the VFS for the CI case.
3158 */
3159 if (IS_CASEFOLDED(dir))
3160 d_invalidate(dentry);
3161 #endif
3162
3163 end_unlink:
3164 brelse(bh);
3165 if (handle)
3166 ext4_journal_stop(handle);
3167 trace_ext4_unlink_exit(dentry, retval);
3168 return retval;
3169 }
3170
3171 static int ext4_symlink(struct inode *dir,
3172 struct dentry *dentry, const char *symname)
3173 {
3174 handle_t *handle;
3175 struct inode *inode;
3176 int err, len = strlen(symname);
3177 int credits;
3178 struct fscrypt_str disk_link;
3179
3180 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3181 return -EIO;
3182
3183 err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,
3184 &disk_link);
3185 if (err)
3186 return err;
3187
3188 err = dquot_initialize(dir);
3189 if (err)
3190 return err;
3191
3192 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3193 /*
3194 * For non-fast symlinks, we just allocate inode and put it on
3195 * orphan list in the first transaction => we need bitmap,
3196 * group descriptor, sb, inode block, quota blocks, and
3197 * possibly selinux xattr blocks.
3198 */
3199 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
3200 EXT4_XATTR_TRANS_BLOCKS;
3201 } else {
3202 /*
3203 * Fast symlink. We have to add entry to directory
3204 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
3205 * allocate new inode (bitmap, group descriptor, inode block,
3206 * quota blocks, sb is already counted in previous macros).
3207 */
3208 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3209 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
3210 }
3211
3212 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
3213 &dentry->d_name, 0, NULL,
3214 EXT4_HT_DIR, credits);
3215 handle = ext4_journal_current_handle();
3216 if (IS_ERR(inode)) {
3217 if (handle)
3218 ext4_journal_stop(handle);
3219 return PTR_ERR(inode);
3220 }
3221
3222 if (IS_ENCRYPTED(inode)) {
3223 err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
3224 if (err)
3225 goto err_drop_inode;
3226 inode->i_op = &ext4_encrypted_symlink_inode_operations;
3227 }
3228
3229 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3230 if (!IS_ENCRYPTED(inode))
3231 inode->i_op = &ext4_symlink_inode_operations;
3232 inode_nohighmem(inode);
3233 ext4_set_aops(inode);
3234 /*
3235 * We cannot call page_symlink() with transaction started
3236 * because it calls into ext4_write_begin() which can wait
3237 * for transaction commit if we are running out of space
3238 * and thus we deadlock. So we have to stop transaction now
3239 * and restart it when symlink contents is written.
3240 *
3241 * To keep fs consistent in case of crash, we have to put inode
3242 * to orphan list in the mean time.
3243 */
3244 drop_nlink(inode);
3245 err = ext4_orphan_add(handle, inode);
3246 ext4_journal_stop(handle);
3247 handle = NULL;
3248 if (err)
3249 goto err_drop_inode;
3250 err = __page_symlink(inode, disk_link.name, disk_link.len, 1);
3251 if (err)
3252 goto err_drop_inode;
3253 /*
3254 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
3255 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
3256 */
3257 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3258 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3259 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
3260 if (IS_ERR(handle)) {
3261 err = PTR_ERR(handle);
3262 handle = NULL;
3263 goto err_drop_inode;
3264 }
3265 set_nlink(inode, 1);
3266 err = ext4_orphan_del(handle, inode);
3267 if (err)
3268 goto err_drop_inode;
3269 } else {
3270 /* clear the extent format for fast symlink */
3271 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
3272 if (!IS_ENCRYPTED(inode)) {
3273 inode->i_op = &ext4_fast_symlink_inode_operations;
3274 inode->i_link = (char *)&EXT4_I(inode)->i_data;
3275 }
3276 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name,
3277 disk_link.len);
3278 inode->i_size = disk_link.len - 1;
3279 }
3280 EXT4_I(inode)->i_disksize = inode->i_size;
3281 err = ext4_add_nondir(handle, dentry, inode);
3282 if (!err && IS_DIRSYNC(dir))
3283 ext4_handle_sync(handle);
3284
3285 if (handle)
3286 ext4_journal_stop(handle);
3287 goto out_free_encrypted_link;
3288
3289 err_drop_inode:
3290 if (handle)
3291 ext4_journal_stop(handle);
3292 clear_nlink(inode);
3293 unlock_new_inode(inode);
3294 iput(inode);
3295 out_free_encrypted_link:
3296 if (disk_link.name != (unsigned char *)symname)
3297 kfree(disk_link.name);
3298 return err;
3299 }
3300
3301 static int ext4_link(struct dentry *old_dentry,
3302 struct inode *dir, struct dentry *dentry)
3303 {
3304 handle_t *handle;
3305 struct inode *inode = d_inode(old_dentry);
3306 int err, retries = 0;
3307
3308 if (inode->i_nlink >= EXT4_LINK_MAX)
3309 return -EMLINK;
3310
3311 err = fscrypt_prepare_link(old_dentry, dir, dentry);
3312 if (err)
3313 return err;
3314
3315 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) &&
3316 (!projid_eq(EXT4_I(dir)->i_projid,
3317 EXT4_I(old_dentry->d_inode)->i_projid)))
3318 return -EXDEV;
3319
3320 err = dquot_initialize(dir);
3321 if (err)
3322 return err;
3323
3324 retry:
3325 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3326 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3327 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
3328 if (IS_ERR(handle))
3329 return PTR_ERR(handle);
3330
3331 if (IS_DIRSYNC(dir))
3332 ext4_handle_sync(handle);
3333
3334 inode->i_ctime = current_time(inode);
3335 ext4_inc_count(handle, inode);
3336 ihold(inode);
3337
3338 err = ext4_add_entry(handle, dentry, inode);
3339 if (!err) {
3340 ext4_mark_inode_dirty(handle, inode);
3341 /* this can happen only for tmpfile being
3342 * linked the first time
3343 */
3344 if (inode->i_nlink == 1)
3345 ext4_orphan_del(handle, inode);
3346 d_instantiate(dentry, inode);
3347 } else {
3348 drop_nlink(inode);
3349 iput(inode);
3350 }
3351 ext4_journal_stop(handle);
3352 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
3353 goto retry;
3354 return err;
3355 }
3356
3357
3358 /*
3359 * Try to find buffer head where contains the parent block.
3360 * It should be the inode block if it is inlined or the 1st block
3361 * if it is a normal dir.
3362 */
3363 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
3364 struct inode *inode,
3365 int *retval,
3366 struct ext4_dir_entry_2 **parent_de,
3367 int *inlined)
3368 {
3369 struct buffer_head *bh;
3370
3371 if (!ext4_has_inline_data(inode)) {
3372 bh = ext4_read_dirblock(inode, 0, EITHER);
3373 if (IS_ERR(bh)) {
3374 *retval = PTR_ERR(bh);
3375 return NULL;
3376 }
3377 *parent_de = ext4_next_entry(
3378 (struct ext4_dir_entry_2 *)bh->b_data,
3379 inode->i_sb->s_blocksize);
3380 return bh;
3381 }
3382
3383 *inlined = 1;
3384 return ext4_get_first_inline_block(inode, parent_de, retval);
3385 }
3386
3387 struct ext4_renament {
3388 struct inode *dir;
3389 struct dentry *dentry;
3390 struct inode *inode;
3391 bool is_dir;
3392 int dir_nlink_delta;
3393
3394 /* entry for "dentry" */
3395 struct buffer_head *bh;
3396 struct ext4_dir_entry_2 *de;
3397 int inlined;
3398
3399 /* entry for ".." in inode if it's a directory */
3400 struct buffer_head *dir_bh;
3401 struct ext4_dir_entry_2 *parent_de;
3402 int dir_inlined;
3403 };
3404
3405 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
3406 {
3407 int retval;
3408
3409 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
3410 &retval, &ent->parent_de,
3411 &ent->dir_inlined);
3412 if (!ent->dir_bh)
3413 return retval;
3414 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
3415 return -EFSCORRUPTED;
3416 BUFFER_TRACE(ent->dir_bh, "get_write_access");
3417 return ext4_journal_get_write_access(handle, ent->dir_bh);
3418 }
3419
3420 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
3421 unsigned dir_ino)
3422 {
3423 int retval;
3424
3425 ent->parent_de->inode = cpu_to_le32(dir_ino);
3426 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
3427 if (!ent->dir_inlined) {
3428 if (is_dx(ent->inode)) {
3429 retval = ext4_handle_dirty_dx_node(handle,
3430 ent->inode,
3431 ent->dir_bh);
3432 } else {
3433 retval = ext4_handle_dirty_dirent_node(handle,
3434 ent->inode,
3435 ent->dir_bh);
3436 }
3437 } else {
3438 retval = ext4_mark_inode_dirty(handle, ent->inode);
3439 }
3440 if (retval) {
3441 ext4_std_error(ent->dir->i_sb, retval);
3442 return retval;
3443 }
3444 return 0;
3445 }
3446
3447 static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
3448 unsigned ino, unsigned file_type)
3449 {
3450 int retval;
3451
3452 BUFFER_TRACE(ent->bh, "get write access");
3453 retval = ext4_journal_get_write_access(handle, ent->bh);
3454 if (retval)
3455 return retval;
3456 ent->de->inode = cpu_to_le32(ino);
3457 if (ext4_has_feature_filetype(ent->dir->i_sb))
3458 ent->de->file_type = file_type;
3459 inode_inc_iversion(ent->dir);
3460 ent->dir->i_ctime = ent->dir->i_mtime =
3461 current_time(ent->dir);
3462 ext4_mark_inode_dirty(handle, ent->dir);
3463 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
3464 if (!ent->inlined) {
3465 retval = ext4_handle_dirty_dirent_node(handle,
3466 ent->dir, ent->bh);
3467 if (unlikely(retval)) {
3468 ext4_std_error(ent->dir->i_sb, retval);
3469 return retval;
3470 }
3471 }
3472 brelse(ent->bh);
3473 ent->bh = NULL;
3474
3475 return 0;
3476 }
3477
3478 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
3479 const struct qstr *d_name)
3480 {
3481 int retval = -ENOENT;
3482 struct buffer_head *bh;
3483 struct ext4_dir_entry_2 *de;
3484
3485 bh = ext4_find_entry(dir, d_name, &de, NULL);
3486 if (IS_ERR(bh))
3487 return PTR_ERR(bh);
3488 if (bh) {
3489 retval = ext4_delete_entry(handle, dir, de, bh);
3490 brelse(bh);
3491 }
3492 return retval;
3493 }
3494
3495 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent,
3496 int force_reread)
3497 {
3498 int retval;
3499 /*
3500 * ent->de could have moved from under us during htree split, so make
3501 * sure that we are deleting the right entry. We might also be pointing
3502 * to a stale entry in the unused part of ent->bh so just checking inum
3503 * and the name isn't enough.
3504 */
3505 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
3506 ent->de->name_len != ent->dentry->d_name.len ||
3507 strncmp(ent->de->name, ent->dentry->d_name.name,
3508 ent->de->name_len) ||
3509 force_reread) {
3510 retval = ext4_find_delete_entry(handle, ent->dir,
3511 &ent->dentry->d_name);
3512 } else {
3513 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
3514 if (retval == -ENOENT) {
3515 retval = ext4_find_delete_entry(handle, ent->dir,
3516 &ent->dentry->d_name);
3517 }
3518 }
3519
3520 if (retval) {
3521 ext4_warning_inode(ent->dir,
3522 "Deleting old file: nlink %d, error=%d",
3523 ent->dir->i_nlink, retval);
3524 }
3525 }
3526
3527 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
3528 {
3529 if (ent->dir_nlink_delta) {
3530 if (ent->dir_nlink_delta == -1)
3531 ext4_dec_count(handle, ent->dir);
3532 else
3533 ext4_inc_count(handle, ent->dir);
3534 ext4_mark_inode_dirty(handle, ent->dir);
3535 }
3536 }
3537
3538 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
3539 int credits, handle_t **h)
3540 {
3541 struct inode *wh;
3542 handle_t *handle;
3543 int retries = 0;
3544
3545 /*
3546 * for inode block, sb block, group summaries,
3547 * and inode bitmap
3548 */
3549 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
3550 EXT4_XATTR_TRANS_BLOCKS + 4);
3551 retry:
3552 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE,
3553 &ent->dentry->d_name, 0, NULL,
3554 EXT4_HT_DIR, credits);
3555
3556 handle = ext4_journal_current_handle();
3557 if (IS_ERR(wh)) {
3558 if (handle)
3559 ext4_journal_stop(handle);
3560 if (PTR_ERR(wh) == -ENOSPC &&
3561 ext4_should_retry_alloc(ent->dir->i_sb, &retries))
3562 goto retry;
3563 } else {
3564 *h = handle;
3565 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);
3566 wh->i_op = &ext4_special_inode_operations;
3567 }
3568 return wh;
3569 }
3570
3571 /*
3572 * Anybody can rename anything with this: the permission checks are left to the
3573 * higher-level routines.
3574 *
3575 * n.b. old_{dentry,inode) refers to the source dentry/inode
3576 * while new_{dentry,inode) refers to the destination dentry/inode
3577 * This comes from rename(const char *oldpath, const char *newpath)
3578 */
3579 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
3580 struct inode *new_dir, struct dentry *new_dentry,
3581 unsigned int flags)
3582 {
3583 handle_t *handle = NULL;
3584 struct ext4_renament old = {
3585 .dir = old_dir,
3586 .dentry = old_dentry,
3587 .inode = d_inode(old_dentry),
3588 };
3589 struct ext4_renament new = {
3590 .dir = new_dir,
3591 .dentry = new_dentry,
3592 .inode = d_inode(new_dentry),
3593 };
3594 int force_reread;
3595 int retval;
3596 struct inode *whiteout = NULL;
3597 int credits;
3598 u8 old_file_type;
3599
3600 if (new.inode && new.inode->i_nlink == 0) {
3601 EXT4_ERROR_INODE(new.inode,
3602 "target of rename is already freed");
3603 return -EFSCORRUPTED;
3604 }
3605
3606 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) &&
3607 (!projid_eq(EXT4_I(new_dir)->i_projid,
3608 EXT4_I(old_dentry->d_inode)->i_projid)))
3609 return -EXDEV;
3610
3611 retval = dquot_initialize(old.dir);
3612 if (retval)
3613 return retval;
3614 retval = dquot_initialize(new.dir);
3615 if (retval)
3616 return retval;
3617
3618 /* Initialize quotas before so that eventual writes go
3619 * in separate transaction */
3620 if (new.inode) {
3621 retval = dquot_initialize(new.inode);
3622 if (retval)
3623 return retval;
3624 }
3625
3626 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
3627 if (IS_ERR(old.bh))
3628 return PTR_ERR(old.bh);
3629 /*
3630 * Check for inode number is _not_ due to possible IO errors.
3631 * We might rmdir the source, keep it as pwd of some process
3632 * and merrily kill the link to whatever was created under the
3633 * same name. Goodbye sticky bit ;-<
3634 */
3635 retval = -ENOENT;
3636 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3637 goto end_rename;
3638
3639 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3640 &new.de, &new.inlined);
3641 if (IS_ERR(new.bh)) {
3642 retval = PTR_ERR(new.bh);
3643 new.bh = NULL;
3644 goto end_rename;
3645 }
3646 if (new.bh) {
3647 if (!new.inode) {
3648 brelse(new.bh);
3649 new.bh = NULL;
3650 }
3651 }
3652 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
3653 ext4_alloc_da_blocks(old.inode);
3654
3655 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3656 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
3657 if (!(flags & RENAME_WHITEOUT)) {
3658 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);
3659 if (IS_ERR(handle)) {
3660 retval = PTR_ERR(handle);
3661 handle = NULL;
3662 goto end_rename;
3663 }
3664 } else {
3665 whiteout = ext4_whiteout_for_rename(&old, credits, &handle);
3666 if (IS_ERR(whiteout)) {
3667 retval = PTR_ERR(whiteout);
3668 whiteout = NULL;
3669 goto end_rename;
3670 }
3671 }
3672
3673 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3674 ext4_handle_sync(handle);
3675
3676 if (S_ISDIR(old.inode->i_mode)) {
3677 if (new.inode) {
3678 retval = -ENOTEMPTY;
3679 if (!ext4_empty_dir(new.inode))
3680 goto end_rename;
3681 } else {
3682 retval = -EMLINK;
3683 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
3684 goto end_rename;
3685 }
3686 retval = ext4_rename_dir_prepare(handle, &old);
3687 if (retval)
3688 goto end_rename;
3689 }
3690 /*
3691 * If we're renaming a file within an inline_data dir and adding or
3692 * setting the new dirent causes a conversion from inline_data to
3693 * extents/blockmap, we need to force the dirent delete code to
3694 * re-read the directory, or else we end up trying to delete a dirent
3695 * from what is now the extent tree root (or a block map).
3696 */
3697 force_reread = (new.dir->i_ino == old.dir->i_ino &&
3698 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA));
3699
3700 old_file_type = old.de->file_type;
3701 if (whiteout) {
3702 /*
3703 * Do this before adding a new entry, so the old entry is sure
3704 * to be still pointing to the valid old entry.
3705 */
3706 retval = ext4_setent(handle, &old, whiteout->i_ino,
3707 EXT4_FT_CHRDEV);
3708 if (retval)
3709 goto end_rename;
3710 ext4_mark_inode_dirty(handle, whiteout);
3711 }
3712 if (!new.bh) {
3713 retval = ext4_add_entry(handle, new.dentry, old.inode);
3714 if (retval)
3715 goto end_rename;
3716 } else {
3717 retval = ext4_setent(handle, &new,
3718 old.inode->i_ino, old_file_type);
3719 if (retval)
3720 goto end_rename;
3721 }
3722 if (force_reread)
3723 force_reread = !ext4_test_inode_flag(new.dir,
3724 EXT4_INODE_INLINE_DATA);
3725
3726 /*
3727 * Like most other Unix systems, set the ctime for inodes on a
3728 * rename.
3729 */
3730 old.inode->i_ctime = current_time(old.inode);
3731 ext4_mark_inode_dirty(handle, old.inode);
3732
3733 if (!whiteout) {
3734 /*
3735 * ok, that's it
3736 */
3737 ext4_rename_delete(handle, &old, force_reread);
3738 }
3739
3740 if (new.inode) {
3741 ext4_dec_count(handle, new.inode);
3742 new.inode->i_ctime = current_time(new.inode);
3743 }
3744 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir);
3745 ext4_update_dx_flag(old.dir);
3746 if (old.dir_bh) {
3747 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3748 if (retval)
3749 goto end_rename;
3750
3751 ext4_dec_count(handle, old.dir);
3752 if (new.inode) {
3753 /* checked ext4_empty_dir above, can't have another
3754 * parent, ext4_dec_count() won't work for many-linked
3755 * dirs */
3756 clear_nlink(new.inode);
3757 } else {
3758 ext4_inc_count(handle, new.dir);
3759 ext4_update_dx_flag(new.dir);
3760 ext4_mark_inode_dirty(handle, new.dir);
3761 }
3762 }
3763 ext4_mark_inode_dirty(handle, old.dir);
3764 if (new.inode) {
3765 ext4_mark_inode_dirty(handle, new.inode);
3766 if (!new.inode->i_nlink)
3767 ext4_orphan_add(handle, new.inode);
3768 }
3769 retval = 0;
3770
3771 end_rename:
3772 brelse(old.dir_bh);
3773 brelse(old.bh);
3774 brelse(new.bh);
3775 if (whiteout) {
3776 if (retval)
3777 drop_nlink(whiteout);
3778 unlock_new_inode(whiteout);
3779 iput(whiteout);
3780 }
3781 if (handle)
3782 ext4_journal_stop(handle);
3783 return retval;
3784 }
3785
3786 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
3787 struct inode *new_dir, struct dentry *new_dentry)
3788 {
3789 handle_t *handle = NULL;
3790 struct ext4_renament old = {
3791 .dir = old_dir,
3792 .dentry = old_dentry,
3793 .inode = d_inode(old_dentry),
3794 };
3795 struct ext4_renament new = {
3796 .dir = new_dir,
3797 .dentry = new_dentry,
3798 .inode = d_inode(new_dentry),
3799 };
3800 u8 new_file_type;
3801 int retval;
3802 struct timespec64 ctime;
3803
3804 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&
3805 !projid_eq(EXT4_I(new_dir)->i_projid,
3806 EXT4_I(old_dentry->d_inode)->i_projid)) ||
3807 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) &&
3808 !projid_eq(EXT4_I(old_dir)->i_projid,
3809 EXT4_I(new_dentry->d_inode)->i_projid)))
3810 return -EXDEV;
3811
3812 retval = dquot_initialize(old.dir);
3813 if (retval)
3814 return retval;
3815 retval = dquot_initialize(new.dir);
3816 if (retval)
3817 return retval;
3818
3819 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
3820 &old.de, &old.inlined);
3821 if (IS_ERR(old.bh))
3822 return PTR_ERR(old.bh);
3823 /*
3824 * Check for inode number is _not_ due to possible IO errors.
3825 * We might rmdir the source, keep it as pwd of some process
3826 * and merrily kill the link to whatever was created under the
3827 * same name. Goodbye sticky bit ;-<
3828 */
3829 retval = -ENOENT;
3830 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3831 goto end_rename;
3832
3833 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3834 &new.de, &new.inlined);
3835 if (IS_ERR(new.bh)) {
3836 retval = PTR_ERR(new.bh);
3837 new.bh = NULL;
3838 goto end_rename;
3839 }
3840
3841 /* RENAME_EXCHANGE case: old *and* new must both exist */
3842 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
3843 goto end_rename;
3844
3845 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
3846 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3847 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
3848 if (IS_ERR(handle)) {
3849 retval = PTR_ERR(handle);
3850 handle = NULL;
3851 goto end_rename;
3852 }
3853
3854 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3855 ext4_handle_sync(handle);
3856
3857 if (S_ISDIR(old.inode->i_mode)) {
3858 old.is_dir = true;
3859 retval = ext4_rename_dir_prepare(handle, &old);
3860 if (retval)
3861 goto end_rename;
3862 }
3863 if (S_ISDIR(new.inode->i_mode)) {
3864 new.is_dir = true;
3865 retval = ext4_rename_dir_prepare(handle, &new);
3866 if (retval)
3867 goto end_rename;
3868 }
3869
3870 /*
3871 * Other than the special case of overwriting a directory, parents'
3872 * nlink only needs to be modified if this is a cross directory rename.
3873 */
3874 if (old.dir != new.dir && old.is_dir != new.is_dir) {
3875 old.dir_nlink_delta = old.is_dir ? -1 : 1;
3876 new.dir_nlink_delta = -old.dir_nlink_delta;
3877 retval = -EMLINK;
3878 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
3879 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
3880 goto end_rename;
3881 }
3882
3883 new_file_type = new.de->file_type;
3884 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
3885 if (retval)
3886 goto end_rename;
3887
3888 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
3889 if (retval)
3890 goto end_rename;
3891
3892 /*
3893 * Like most other Unix systems, set the ctime for inodes on a
3894 * rename.
3895 */
3896 ctime = current_time(old.inode);
3897 old.inode->i_ctime = ctime;
3898 new.inode->i_ctime = ctime;
3899 ext4_mark_inode_dirty(handle, old.inode);
3900 ext4_mark_inode_dirty(handle, new.inode);
3901
3902 if (old.dir_bh) {
3903 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3904 if (retval)
3905 goto end_rename;
3906 }
3907 if (new.dir_bh) {
3908 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
3909 if (retval)
3910 goto end_rename;
3911 }
3912 ext4_update_dir_count(handle, &old);
3913 ext4_update_dir_count(handle, &new);
3914 retval = 0;
3915
3916 end_rename:
3917 brelse(old.dir_bh);
3918 brelse(new.dir_bh);
3919 brelse(old.bh);
3920 brelse(new.bh);
3921 if (handle)
3922 ext4_journal_stop(handle);
3923 return retval;
3924 }
3925
3926 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
3927 struct inode *new_dir, struct dentry *new_dentry,
3928 unsigned int flags)
3929 {
3930 int err;
3931
3932 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb))))
3933 return -EIO;
3934
3935 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
3936 return -EINVAL;
3937
3938 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
3939 flags);
3940 if (err)
3941 return err;
3942
3943 if (flags & RENAME_EXCHANGE) {
3944 return ext4_cross_rename(old_dir, old_dentry,
3945 new_dir, new_dentry);
3946 }
3947
3948 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
3949 }
3950
3951 /*
3952 * directories can handle most operations...
3953 */
3954 const struct inode_operations ext4_dir_inode_operations = {
3955 .create = ext4_create,
3956 .lookup = ext4_lookup,
3957 .link = ext4_link,
3958 .unlink = ext4_unlink,
3959 .symlink = ext4_symlink,
3960 .mkdir = ext4_mkdir,
3961 .rmdir = ext4_rmdir,
3962 .mknod = ext4_mknod,
3963 .tmpfile = ext4_tmpfile,
3964 .rename = ext4_rename2,
3965 .setattr = ext4_setattr,
3966 .getattr = ext4_getattr,
3967 .listxattr = ext4_listxattr,
3968 .get_acl = ext4_get_acl,
3969 .set_acl = ext4_set_acl,
3970 .fiemap = ext4_fiemap,
3971 };
3972
3973 const struct inode_operations ext4_special_inode_operations = {
3974 .setattr = ext4_setattr,
3975 .getattr = ext4_getattr,
3976 .listxattr = ext4_listxattr,
3977 .get_acl = ext4_get_acl,
3978 .set_acl = ext4_set_acl,
3979 };
Mirror of linux-2.6-arm at arm.linux.org.uk