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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
[linux/fpc-iii.git] / fs / ext4 / namei.c
blob153a9fbe1dd06948dd76fa1041c086342d802a19
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 /*
86 * Hints to ext4_read_dirblock regarding whether we expect a directory
87 * block being read to be an index block, or a block containing
88 * directory entries (and if the latter, whether it was found via a
89 * logical block in an htree index block). This is used to control
90 * what sort of sanity checkinig ext4_read_dirblock() will do on the
91 * directory block read from the storage device. EITHER will means
92 * the caller doesn't know what kind of directory block will be read,
93 * so no specific verification will be done.
94 */
95 typedef enum {
96 EITHER, INDEX, DIRENT, DIRENT_HTREE
97 } dirblock_type_t;
98
99 #define ext4_read_dirblock(inode, block, type) \
100 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__)
101
102 static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
103 ext4_lblk_t block,
104 dirblock_type_t type,
105 const char *func,
106 unsigned int line)
107 {
108 struct buffer_head *bh;
109 struct ext4_dir_entry *dirent;
110 int is_dx_block = 0;
111
112 if (ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_EIO))
113 bh = ERR_PTR(-EIO);
114 else
115 bh = ext4_bread(NULL, inode, block, 0);
116 if (IS_ERR(bh)) {
117 __ext4_warning(inode->i_sb, func, line,
118 "inode #%lu: lblock %lu: comm %s: "
119 "error %ld reading directory block",
120 inode->i_ino, (unsigned long)block,
121 current->comm, PTR_ERR(bh));
122
123 return bh;
124 }
125 if (!bh && (type == INDEX || type == DIRENT_HTREE)) {
126 ext4_error_inode(inode, func, line, block,
127 "Directory hole found for htree %s block",
128 (type == INDEX) ? "index" : "leaf");
129 return ERR_PTR(-EFSCORRUPTED);
130 }
131 if (!bh)
132 return NULL;
133 dirent = (struct ext4_dir_entry *) bh->b_data;
134 /* Determine whether or not we have an index block */
135 if (is_dx(inode)) {
136 if (block == 0)
137 is_dx_block = 1;
138 else if (ext4_rec_len_from_disk(dirent->rec_len,
139 inode->i_sb->s_blocksize) ==
140 inode->i_sb->s_blocksize)
141 is_dx_block = 1;
142 }
143 if (!is_dx_block && type == INDEX) {
144 ext4_error_inode(inode, func, line, block,
145 "directory leaf block found instead of index block");
146 brelse(bh);
147 return ERR_PTR(-EFSCORRUPTED);
148 }
149 if (!ext4_has_metadata_csum(inode->i_sb) ||
150 buffer_verified(bh))
151 return bh;
152
153 /*
154 * An empty leaf block can get mistaken for a index block; for
155 * this reason, we can only check the index checksum when the
156 * caller is sure it should be an index block.
157 */
158 if (is_dx_block && type == INDEX) {
159 if (ext4_dx_csum_verify(inode, dirent) &&
160 !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))
161 set_buffer_verified(bh);
162 else {
163 ext4_error_inode_err(inode, func, line, block,
164 EFSBADCRC,
165 "Directory index failed checksum");
166 brelse(bh);
167 return ERR_PTR(-EFSBADCRC);
168 }
169 }
170 if (!is_dx_block) {
171 if (ext4_dirblock_csum_verify(inode, bh) &&
172 !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))
173 set_buffer_verified(bh);
174 else {
175 ext4_error_inode_err(inode, func, line, block,
176 EFSBADCRC,
177 "Directory block failed checksum");
178 brelse(bh);
179 return ERR_PTR(-EFSBADCRC);
180 }
181 }
182 return bh;
183 }
184
185 #ifndef assert
186 #define assert(test) J_ASSERT(test)
187 #endif
188
189 #ifdef DX_DEBUG
190 #define dxtrace(command) command
191 #else
192 #define dxtrace(command)
193 #endif
194
195 struct fake_dirent
196 {
197 __le32 inode;
198 __le16 rec_len;
199 u8 name_len;
200 u8 file_type;
201 };
202
203 struct dx_countlimit
204 {
205 __le16 limit;
206 __le16 count;
207 };
208
209 struct dx_entry
210 {
211 __le32 hash;
212 __le32 block;
213 };
214
215 /*
216 * dx_root_info is laid out so that if it should somehow get overlaid by a
217 * dirent the two low bits of the hash version will be zero. Therefore, the
218 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
219 */
220
221 struct dx_root
222 {
223 struct fake_dirent dot;
224 char dot_name[4];
225 struct fake_dirent dotdot;
226 char dotdot_name[4];
227 struct dx_root_info
228 {
229 __le32 reserved_zero;
230 u8 hash_version;
231 u8 info_length; /* 8 */
232 u8 indirect_levels;
233 u8 unused_flags;
234 }
235 info;
236 struct dx_entry entries[];
237 };
238
239 struct dx_node
240 {
241 struct fake_dirent fake;
242 struct dx_entry entries[];
243 };
244
245
246 struct dx_frame
247 {
248 struct buffer_head *bh;
249 struct dx_entry *entries;
250 struct dx_entry *at;
251 };
252
253 struct dx_map_entry
254 {
255 u32 hash;
256 u16 offs;
257 u16 size;
258 };
259
260 /*
261 * This goes at the end of each htree block.
262 */
263 struct dx_tail {
264 u32 dt_reserved;
265 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
266 };
267
268 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
269 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
270 static inline unsigned dx_get_hash(struct dx_entry *entry);
271 static void dx_set_hash(struct dx_entry *entry, unsigned value);
272 static unsigned dx_get_count(struct dx_entry *entries);
273 static unsigned dx_get_limit(struct dx_entry *entries);
274 static void dx_set_count(struct dx_entry *entries, unsigned value);
275 static void dx_set_limit(struct dx_entry *entries, unsigned value);
276 static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
277 static unsigned dx_node_limit(struct inode *dir);
278 static struct dx_frame *dx_probe(struct ext4_filename *fname,
279 struct inode *dir,
280 struct dx_hash_info *hinfo,
281 struct dx_frame *frame);
282 static void dx_release(struct dx_frame *frames);
283 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
284 unsigned blocksize, struct dx_hash_info *hinfo,
285 struct dx_map_entry map[]);
286 static void dx_sort_map(struct dx_map_entry *map, unsigned count);
287 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
288 struct dx_map_entry *offsets, int count, unsigned blocksize);
289 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
290 static void dx_insert_block(struct dx_frame *frame,
291 u32 hash, ext4_lblk_t block);
292 static int ext4_htree_next_block(struct inode *dir, __u32 hash,
293 struct dx_frame *frame,
294 struct dx_frame *frames,
295 __u32 *start_hash);
296 static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
297 struct ext4_filename *fname,
298 struct ext4_dir_entry_2 **res_dir);
299 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
300 struct inode *dir, struct inode *inode);
301
302 /* checksumming functions */
303 void ext4_initialize_dirent_tail(struct buffer_head *bh,
304 unsigned int blocksize)
305 {
306 struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
307
308 memset(t, 0, sizeof(struct ext4_dir_entry_tail));
309 t->det_rec_len = ext4_rec_len_to_disk(
310 sizeof(struct ext4_dir_entry_tail), blocksize);
311 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
312 }
313
314 /* Walk through a dirent block to find a checksum "dirent" at the tail */
315 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
316 struct buffer_head *bh)
317 {
318 struct ext4_dir_entry_tail *t;
319
320 #ifdef PARANOID
321 struct ext4_dir_entry *d, *top;
322
323 d = (struct ext4_dir_entry *)bh->b_data;
324 top = (struct ext4_dir_entry *)(bh->b_data +
325 (EXT4_BLOCK_SIZE(inode->i_sb) -
326 sizeof(struct ext4_dir_entry_tail)));
327 while (d < top && d->rec_len)
328 d = (struct ext4_dir_entry *)(((void *)d) +
329 le16_to_cpu(d->rec_len));
330
331 if (d != top)
332 return NULL;
333
334 t = (struct ext4_dir_entry_tail *)d;
335 #else
336 t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb));
337 #endif
338
339 if (t->det_reserved_zero1 ||
340 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
341 t->det_reserved_zero2 ||
342 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
343 return NULL;
344
345 return t;
346 }
347
348 static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size)
349 {
350 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
351 struct ext4_inode_info *ei = EXT4_I(inode);
352 __u32 csum;
353
354 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
355 return cpu_to_le32(csum);
356 }
357
358 #define warn_no_space_for_csum(inode) \
359 __warn_no_space_for_csum((inode), __func__, __LINE__)
360
361 static void __warn_no_space_for_csum(struct inode *inode, const char *func,
362 unsigned int line)
363 {
364 __ext4_warning_inode(inode, func, line,
365 "No space for directory leaf checksum. Please run e2fsck -D.");
366 }
367
368 int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)
369 {
370 struct ext4_dir_entry_tail *t;
371
372 if (!ext4_has_metadata_csum(inode->i_sb))
373 return 1;
374
375 t = get_dirent_tail(inode, bh);
376 if (!t) {
377 warn_no_space_for_csum(inode);
378 return 0;
379 }
380
381 if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data,
382 (char *)t - bh->b_data))
383 return 0;
384
385 return 1;
386 }
387
388 static void ext4_dirblock_csum_set(struct inode *inode,
389 struct buffer_head *bh)
390 {
391 struct ext4_dir_entry_tail *t;
392
393 if (!ext4_has_metadata_csum(inode->i_sb))
394 return;
395
396 t = get_dirent_tail(inode, bh);
397 if (!t) {
398 warn_no_space_for_csum(inode);
399 return;
400 }
401
402 t->det_checksum = ext4_dirblock_csum(inode, bh->b_data,
403 (char *)t - bh->b_data);
404 }
405
406 int ext4_handle_dirty_dirblock(handle_t *handle,
407 struct inode *inode,
408 struct buffer_head *bh)
409 {
410 ext4_dirblock_csum_set(inode, bh);
411 return ext4_handle_dirty_metadata(handle, inode, bh);
412 }
413
414 static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
415 struct ext4_dir_entry *dirent,
416 int *offset)
417 {
418 struct ext4_dir_entry *dp;
419 struct dx_root_info *root;
420 int count_offset;
421
422 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
423 count_offset = 8;
424 else if (le16_to_cpu(dirent->rec_len) == 12) {
425 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
426 if (le16_to_cpu(dp->rec_len) !=
427 EXT4_BLOCK_SIZE(inode->i_sb) - 12)
428 return NULL;
429 root = (struct dx_root_info *)(((void *)dp + 12));
430 if (root->reserved_zero ||
431 root->info_length != sizeof(struct dx_root_info))
432 return NULL;
433 count_offset = 32;
434 } else
435 return NULL;
436
437 if (offset)
438 *offset = count_offset;
439 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
440 }
441
442 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
443 int count_offset, int count, struct dx_tail *t)
444 {
445 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
446 struct ext4_inode_info *ei = EXT4_I(inode);
447 __u32 csum;
448 int size;
449 __u32 dummy_csum = 0;
450 int offset = offsetof(struct dx_tail, dt_checksum);
451
452 size = count_offset + (count * sizeof(struct dx_entry));
453 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
454 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset);
455 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
456
457 return cpu_to_le32(csum);
458 }
459
460 static int ext4_dx_csum_verify(struct inode *inode,
461 struct ext4_dir_entry *dirent)
462 {
463 struct dx_countlimit *c;
464 struct dx_tail *t;
465 int count_offset, limit, count;
466
467 if (!ext4_has_metadata_csum(inode->i_sb))
468 return 1;
469
470 c = get_dx_countlimit(inode, dirent, &count_offset);
471 if (!c) {
472 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
473 return 0;
474 }
475 limit = le16_to_cpu(c->limit);
476 count = le16_to_cpu(c->count);
477 if (count_offset + (limit * sizeof(struct dx_entry)) >
478 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
479 warn_no_space_for_csum(inode);
480 return 0;
481 }
482 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
483
484 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
485 count, t))
486 return 0;
487 return 1;
488 }
489
490 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
491 {
492 struct dx_countlimit *c;
493 struct dx_tail *t;
494 int count_offset, limit, count;
495
496 if (!ext4_has_metadata_csum(inode->i_sb))
497 return;
498
499 c = get_dx_countlimit(inode, dirent, &count_offset);
500 if (!c) {
501 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
502 return;
503 }
504 limit = le16_to_cpu(c->limit);
505 count = le16_to_cpu(c->count);
506 if (count_offset + (limit * sizeof(struct dx_entry)) >
507 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
508 warn_no_space_for_csum(inode);
509 return;
510 }
511 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
512
513 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
514 }
515
516 static inline int ext4_handle_dirty_dx_node(handle_t *handle,
517 struct inode *inode,
518 struct buffer_head *bh)
519 {
520 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
521 return ext4_handle_dirty_metadata(handle, inode, bh);
522 }
523
524 /*
525 * p is at least 6 bytes before the end of page
526 */
527 static inline struct ext4_dir_entry_2 *
528 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
529 {
530 return (struct ext4_dir_entry_2 *)((char *)p +
531 ext4_rec_len_from_disk(p->rec_len, blocksize));
532 }
533
534 /*
535 * Future: use high four bits of block for coalesce-on-delete flags
536 * Mask them off for now.
537 */
538
539 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
540 {
541 return le32_to_cpu(entry->block) & 0x0fffffff;
542 }
543
544 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
545 {
546 entry->block = cpu_to_le32(value);
547 }
548
549 static inline unsigned dx_get_hash(struct dx_entry *entry)
550 {
551 return le32_to_cpu(entry->hash);
552 }
553
554 static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
555 {
556 entry->hash = cpu_to_le32(value);
557 }
558
559 static inline unsigned dx_get_count(struct dx_entry *entries)
560 {
561 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
562 }
563
564 static inline unsigned dx_get_limit(struct dx_entry *entries)
565 {
566 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
567 }
568
569 static inline void dx_set_count(struct dx_entry *entries, unsigned value)
570 {
571 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
572 }
573
574 static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
575 {
576 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
577 }
578
579 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
580 {
581 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
582 EXT4_DIR_REC_LEN(2) - infosize;
583
584 if (ext4_has_metadata_csum(dir->i_sb))
585 entry_space -= sizeof(struct dx_tail);
586 return entry_space / sizeof(struct dx_entry);
587 }
588
589 static inline unsigned dx_node_limit(struct inode *dir)
590 {
591 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
592
593 if (ext4_has_metadata_csum(dir->i_sb))
594 entry_space -= sizeof(struct dx_tail);
595 return entry_space / sizeof(struct dx_entry);
596 }
597
598 /*
599 * Debug
600 */
601 #ifdef DX_DEBUG
602 static void dx_show_index(char * label, struct dx_entry *entries)
603 {
604 int i, n = dx_get_count (entries);
605 printk(KERN_DEBUG "%s index", label);
606 for (i = 0; i < n; i++) {
607 printk(KERN_CONT " %x->%lu",
608 i ? dx_get_hash(entries + i) : 0,
609 (unsigned long)dx_get_block(entries + i));
610 }
611 printk(KERN_CONT "\n");
612 }
613
614 struct stats
615 {
616 unsigned names;
617 unsigned space;
618 unsigned bcount;
619 };
620
621 static struct stats dx_show_leaf(struct inode *dir,
622 struct dx_hash_info *hinfo,
623 struct ext4_dir_entry_2 *de,
624 int size, int show_names)
625 {
626 unsigned names = 0, space = 0;
627 char *base = (char *) de;
628 struct dx_hash_info h = *hinfo;
629
630 printk("names: ");
631 while ((char *) de < base + size)
632 {
633 if (de->inode)
634 {
635 if (show_names)
636 {
637 #ifdef CONFIG_FS_ENCRYPTION
638 int len;
639 char *name;
640 struct fscrypt_str fname_crypto_str =
641 FSTR_INIT(NULL, 0);
642 int res = 0;
643
644 name = de->name;
645 len = de->name_len;
646 if (IS_ENCRYPTED(dir))
647 res = fscrypt_get_encryption_info(dir);
648 if (res) {
649 printk(KERN_WARNING "Error setting up"
650 " fname crypto: %d\n", res);
651 }
652 if (!fscrypt_has_encryption_key(dir)) {
653 /* Directory is not encrypted */
654 ext4fs_dirhash(dir, de->name,
655 de->name_len, &h);
656 printk("%*.s:(U)%x.%u ", len,
657 name, h.hash,
658 (unsigned) ((char *) de
659 - base));
660 } else {
661 struct fscrypt_str de_name =
662 FSTR_INIT(name, len);
663
664 /* Directory is encrypted */
665 res = fscrypt_fname_alloc_buffer(
666 dir, len,
667 &fname_crypto_str);
668 if (res)
669 printk(KERN_WARNING "Error "
670 "allocating crypto "
671 "buffer--skipping "
672 "crypto\n");
673 res = fscrypt_fname_disk_to_usr(dir,
674 0, 0, &de_name,
675 &fname_crypto_str);
676 if (res) {
677 printk(KERN_WARNING "Error "
678 "converting filename "
679 "from disk to usr"
680 "\n");
681 name = "??";
682 len = 2;
683 } else {
684 name = fname_crypto_str.name;
685 len = fname_crypto_str.len;
686 }
687 ext4fs_dirhash(dir, de->name,
688 de->name_len, &h);
689 printk("%*.s:(E)%x.%u ", len, name,
690 h.hash, (unsigned) ((char *) de
691 - base));
692 fscrypt_fname_free_buffer(
693 &fname_crypto_str);
694 }
695 #else
696 int len = de->name_len;
697 char *name = de->name;
698 ext4fs_dirhash(dir, de->name, de->name_len, &h);
699 printk("%*.s:%x.%u ", len, name, h.hash,
700 (unsigned) ((char *) de - base));
701 #endif
702 }
703 space += EXT4_DIR_REC_LEN(de->name_len);
704 names++;
705 }
706 de = ext4_next_entry(de, size);
707 }
708 printk(KERN_CONT "(%i)\n", names);
709 return (struct stats) { names, space, 1 };
710 }
711
712 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
713 struct dx_entry *entries, int levels)
714 {
715 unsigned blocksize = dir->i_sb->s_blocksize;
716 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
717 unsigned bcount = 0;
718 struct buffer_head *bh;
719 printk("%i indexed blocks...\n", count);
720 for (i = 0; i < count; i++, entries++)
721 {
722 ext4_lblk_t block = dx_get_block(entries);
723 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
724 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
725 struct stats stats;
726 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
727 bh = ext4_bread(NULL,dir, block, 0);
728 if (!bh || IS_ERR(bh))
729 continue;
730 stats = levels?
731 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
732 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)
733 bh->b_data, blocksize, 0);
734 names += stats.names;
735 space += stats.space;
736 bcount += stats.bcount;
737 brelse(bh);
738 }
739 if (bcount)
740 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
741 levels ? "" : " ", names, space/bcount,
742 (space/bcount)*100/blocksize);
743 return (struct stats) { names, space, bcount};
744 }
745 #endif /* DX_DEBUG */
746
747 /*
748 * Probe for a directory leaf block to search.
749 *
750 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
751 * error in the directory index, and the caller should fall back to
752 * searching the directory normally. The callers of dx_probe **MUST**
753 * check for this error code, and make sure it never gets reflected
754 * back to userspace.
755 */
756 static struct dx_frame *
757 dx_probe(struct ext4_filename *fname, struct inode *dir,
758 struct dx_hash_info *hinfo, struct dx_frame *frame_in)
759 {
760 unsigned count, indirect;
761 struct dx_entry *at, *entries, *p, *q, *m;
762 struct dx_root *root;
763 struct dx_frame *frame = frame_in;
764 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);
765 u32 hash;
766
767 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0]));
768 frame->bh = ext4_read_dirblock(dir, 0, INDEX);
769 if (IS_ERR(frame->bh))
770 return (struct dx_frame *) frame->bh;
771
772 root = (struct dx_root *) frame->bh->b_data;
773 if (root->info.hash_version != DX_HASH_TEA &&
774 root->info.hash_version != DX_HASH_HALF_MD4 &&
775 root->info.hash_version != DX_HASH_LEGACY) {
776 ext4_warning_inode(dir, "Unrecognised inode hash code %u",
777 root->info.hash_version);
778 goto fail;
779 }
780 if (fname)
781 hinfo = &fname->hinfo;
782 hinfo->hash_version = root->info.hash_version;
783 if (hinfo->hash_version <= DX_HASH_TEA)
784 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
785 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
786 if (fname && fname_name(fname))
787 ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), hinfo);
788 hash = hinfo->hash;
789
790 if (root->info.unused_flags & 1) {
791 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x",
792 root->info.unused_flags);
793 goto fail;
794 }
795
796 indirect = root->info.indirect_levels;
797 if (indirect >= ext4_dir_htree_level(dir->i_sb)) {
798 ext4_warning(dir->i_sb,
799 "Directory (ino: %lu) htree depth %#06x exceed"
800 "supported value", dir->i_ino,
801 ext4_dir_htree_level(dir->i_sb));
802 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) {
803 ext4_warning(dir->i_sb, "Enable large directory "
804 "feature to access it");
805 }
806 goto fail;
807 }
808
809 entries = (struct dx_entry *)(((char *)&root->info) +
810 root->info.info_length);
811
812 if (dx_get_limit(entries) != dx_root_limit(dir,
813 root->info.info_length)) {
814 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
815 dx_get_limit(entries),
816 dx_root_limit(dir, root->info.info_length));
817 goto fail;
818 }
819
820 dxtrace(printk("Look up %x", hash));
821 while (1) {
822 count = dx_get_count(entries);
823 if (!count || count > dx_get_limit(entries)) {
824 ext4_warning_inode(dir,
825 "dx entry: count %u beyond limit %u",
826 count, dx_get_limit(entries));
827 goto fail;
828 }
829
830 p = entries + 1;
831 q = entries + count - 1;
832 while (p <= q) {
833 m = p + (q - p) / 2;
834 dxtrace(printk(KERN_CONT "."));
835 if (dx_get_hash(m) > hash)
836 q = m - 1;
837 else
838 p = m + 1;
839 }
840
841 if (0) { // linear search cross check
842 unsigned n = count - 1;
843 at = entries;
844 while (n--)
845 {
846 dxtrace(printk(KERN_CONT ","));
847 if (dx_get_hash(++at) > hash)
848 {
849 at--;
850 break;
851 }
852 }
853 assert (at == p - 1);
854 }
855
856 at = p - 1;
857 dxtrace(printk(KERN_CONT " %x->%u\n",
858 at == entries ? 0 : dx_get_hash(at),
859 dx_get_block(at)));
860 frame->entries = entries;
861 frame->at = at;
862 if (!indirect--)
863 return frame;
864 frame++;
865 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
866 if (IS_ERR(frame->bh)) {
867 ret_err = (struct dx_frame *) frame->bh;
868 frame->bh = NULL;
869 goto fail;
870 }
871 entries = ((struct dx_node *) frame->bh->b_data)->entries;
872
873 if (dx_get_limit(entries) != dx_node_limit(dir)) {
874 ext4_warning_inode(dir,
875 "dx entry: limit %u != node limit %u",
876 dx_get_limit(entries), dx_node_limit(dir));
877 goto fail;
878 }
879 }
880 fail:
881 while (frame >= frame_in) {
882 brelse(frame->bh);
883 frame--;
884 }
885
886 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
887 ext4_warning_inode(dir,
888 "Corrupt directory, running e2fsck is recommended");
889 return ret_err;
890 }
891
892 static void dx_release(struct dx_frame *frames)
893 {
894 struct dx_root_info *info;
895 int i;
896 unsigned int indirect_levels;
897
898 if (frames[0].bh == NULL)
899 return;
900
901 info = &((struct dx_root *)frames[0].bh->b_data)->info;
902 /* save local copy, "info" may be freed after brelse() */
903 indirect_levels = info->indirect_levels;
904 for (i = 0; i <= indirect_levels; i++) {
905 if (frames[i].bh == NULL)
906 break;
907 brelse(frames[i].bh);
908 frames[i].bh = NULL;
909 }
910 }
911
912 /*
913 * This function increments the frame pointer to search the next leaf
914 * block, and reads in the necessary intervening nodes if the search
915 * should be necessary. Whether or not the search is necessary is
916 * controlled by the hash parameter. If the hash value is even, then
917 * the search is only continued if the next block starts with that
918 * hash value. This is used if we are searching for a specific file.
919 *
920 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
921 *
922 * This function returns 1 if the caller should continue to search,
923 * or 0 if it should not. If there is an error reading one of the
924 * index blocks, it will a negative error code.
925 *
926 * If start_hash is non-null, it will be filled in with the starting
927 * hash of the next page.
928 */
929 static int ext4_htree_next_block(struct inode *dir, __u32 hash,
930 struct dx_frame *frame,
931 struct dx_frame *frames,
932 __u32 *start_hash)
933 {
934 struct dx_frame *p;
935 struct buffer_head *bh;
936 int num_frames = 0;
937 __u32 bhash;
938
939 p = frame;
940 /*
941 * Find the next leaf page by incrementing the frame pointer.
942 * If we run out of entries in the interior node, loop around and
943 * increment pointer in the parent node. When we break out of
944 * this loop, num_frames indicates the number of interior
945 * nodes need to be read.
946 */
947 while (1) {
948 if (++(p->at) < p->entries + dx_get_count(p->entries))
949 break;
950 if (p == frames)
951 return 0;
952 num_frames++;
953 p--;
954 }
955
956 /*
957 * If the hash is 1, then continue only if the next page has a
958 * continuation hash of any value. This is used for readdir
959 * handling. Otherwise, check to see if the hash matches the
960 * desired contiuation hash. If it doesn't, return since
961 * there's no point to read in the successive index pages.
962 */
963 bhash = dx_get_hash(p->at);
964 if (start_hash)
965 *start_hash = bhash;
966 if ((hash & 1) == 0) {
967 if ((bhash & ~1) != hash)
968 return 0;
969 }
970 /*
971 * If the hash is HASH_NB_ALWAYS, we always go to the next
972 * block so no check is necessary
973 */
974 while (num_frames--) {
975 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
976 if (IS_ERR(bh))
977 return PTR_ERR(bh);
978 p++;
979 brelse(p->bh);
980 p->bh = bh;
981 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
982 }
983 return 1;
984 }
985
986
987 /*
988 * This function fills a red-black tree with information from a
989 * directory block. It returns the number directory entries loaded
990 * into the tree. If there is an error it is returned in err.
991 */
992 static int htree_dirblock_to_tree(struct file *dir_file,
993 struct inode *dir, ext4_lblk_t block,
994 struct dx_hash_info *hinfo,
995 __u32 start_hash, __u32 start_minor_hash)
996 {
997 struct buffer_head *bh;
998 struct ext4_dir_entry_2 *de, *top;
999 int err = 0, count = 0;
1000 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;
1001
1002 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
1003 (unsigned long)block));
1004 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
1005 if (IS_ERR(bh))
1006 return PTR_ERR(bh);
1007
1008 de = (struct ext4_dir_entry_2 *) bh->b_data;
1009 top = (struct ext4_dir_entry_2 *) ((char *) de +
1010 dir->i_sb->s_blocksize -
1011 EXT4_DIR_REC_LEN(0));
1012 /* Check if the directory is encrypted */
1013 if (IS_ENCRYPTED(dir)) {
1014 err = fscrypt_get_encryption_info(dir);
1015 if (err < 0) {
1016 brelse(bh);
1017 return err;
1018 }
1019 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN,
1020 &fname_crypto_str);
1021 if (err < 0) {
1022 brelse(bh);
1023 return err;
1024 }
1025 }
1026
1027 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
1028 if (ext4_check_dir_entry(dir, NULL, de, bh,
1029 bh->b_data, bh->b_size,
1030 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
1031 + ((char *)de - bh->b_data))) {
1032 /* silently ignore the rest of the block */
1033 break;
1034 }
1035 ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
1036 if ((hinfo->hash < start_hash) ||
1037 ((hinfo->hash == start_hash) &&
1038 (hinfo->minor_hash < start_minor_hash)))
1039 continue;
1040 if (de->inode == 0)
1041 continue;
1042 if (!IS_ENCRYPTED(dir)) {
1043 tmp_str.name = de->name;
1044 tmp_str.len = de->name_len;
1045 err = ext4_htree_store_dirent(dir_file,
1046 hinfo->hash, hinfo->minor_hash, de,
1047 &tmp_str);
1048 } else {
1049 int save_len = fname_crypto_str.len;
1050 struct fscrypt_str de_name = FSTR_INIT(de->name,
1051 de->name_len);
1052
1053 /* Directory is encrypted */
1054 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash,
1055 hinfo->minor_hash, &de_name,
1056 &fname_crypto_str);
1057 if (err) {
1058 count = err;
1059 goto errout;
1060 }
1061 err = ext4_htree_store_dirent(dir_file,
1062 hinfo->hash, hinfo->minor_hash, de,
1063 &fname_crypto_str);
1064 fname_crypto_str.len = save_len;
1065 }
1066 if (err != 0) {
1067 count = err;
1068 goto errout;
1069 }
1070 count++;
1071 }
1072 errout:
1073 brelse(bh);
1074 fscrypt_fname_free_buffer(&fname_crypto_str);
1075 return count;
1076 }
1077
1078
1079 /*
1080 * This function fills a red-black tree with information from a
1081 * directory. We start scanning the directory in hash order, starting
1082 * at start_hash and start_minor_hash.
1083 *
1084 * This function returns the number of entries inserted into the tree,
1085 * or a negative error code.
1086 */
1087 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1088 __u32 start_minor_hash, __u32 *next_hash)
1089 {
1090 struct dx_hash_info hinfo;
1091 struct ext4_dir_entry_2 *de;
1092 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1093 struct inode *dir;
1094 ext4_lblk_t block;
1095 int count = 0;
1096 int ret, err;
1097 __u32 hashval;
1098 struct fscrypt_str tmp_str;
1099
1100 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
1101 start_hash, start_minor_hash));
1102 dir = file_inode(dir_file);
1103 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
1104 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
1105 if (hinfo.hash_version <= DX_HASH_TEA)
1106 hinfo.hash_version +=
1107 EXT4_SB(dir->i_sb)->s_hash_unsigned;
1108 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1109 if (ext4_has_inline_data(dir)) {
1110 int has_inline_data = 1;
1111 count = ext4_inlinedir_to_tree(dir_file, dir, 0,
1112 &hinfo, start_hash,
1113 start_minor_hash,
1114 &has_inline_data);
1115 if (has_inline_data) {
1116 *next_hash = ~0;
1117 return count;
1118 }
1119 }
1120 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
1121 start_hash, start_minor_hash);
1122 *next_hash = ~0;
1123 return count;
1124 }
1125 hinfo.hash = start_hash;
1126 hinfo.minor_hash = 0;
1127 frame = dx_probe(NULL, dir, &hinfo, frames);
1128 if (IS_ERR(frame))
1129 return PTR_ERR(frame);
1130
1131 /* Add '.' and '..' from the htree header */
1132 if (!start_hash && !start_minor_hash) {
1133 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1134 tmp_str.name = de->name;
1135 tmp_str.len = de->name_len;
1136 err = ext4_htree_store_dirent(dir_file, 0, 0,
1137 de, &tmp_str);
1138 if (err != 0)
1139 goto errout;
1140 count++;
1141 }
1142 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
1143 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1144 de = ext4_next_entry(de, dir->i_sb->s_blocksize);
1145 tmp_str.name = de->name;
1146 tmp_str.len = de->name_len;
1147 err = ext4_htree_store_dirent(dir_file, 2, 0,
1148 de, &tmp_str);
1149 if (err != 0)
1150 goto errout;
1151 count++;
1152 }
1153
1154 while (1) {
1155 if (fatal_signal_pending(current)) {
1156 err = -ERESTARTSYS;
1157 goto errout;
1158 }
1159 cond_resched();
1160 block = dx_get_block(frame->at);
1161 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
1162 start_hash, start_minor_hash);
1163 if (ret < 0) {
1164 err = ret;
1165 goto errout;
1166 }
1167 count += ret;
1168 hashval = ~0;
1169 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
1170 frame, frames, &hashval);
1171 *next_hash = hashval;
1172 if (ret < 0) {
1173 err = ret;
1174 goto errout;
1175 }
1176 /*
1177 * Stop if: (a) there are no more entries, or
1178 * (b) we have inserted at least one entry and the
1179 * next hash value is not a continuation
1180 */
1181 if ((ret == 0) ||
1182 (count && ((hashval & 1) == 0)))
1183 break;
1184 }
1185 dx_release(frames);
1186 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1187 "next hash: %x\n", count, *next_hash));
1188 return count;
1189 errout:
1190 dx_release(frames);
1191 return (err);
1192 }
1193
1194 static inline int search_dirblock(struct buffer_head *bh,
1195 struct inode *dir,
1196 struct ext4_filename *fname,
1197 unsigned int offset,
1198 struct ext4_dir_entry_2 **res_dir)
1199 {
1200 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,
1201 fname, offset, res_dir);
1202 }
1203
1204 /*
1205 * Directory block splitting, compacting
1206 */
1207
1208 /*
1209 * Create map of hash values, offsets, and sizes, stored at end of block.
1210 * Returns number of entries mapped.
1211 */
1212 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
1213 unsigned blocksize, struct dx_hash_info *hinfo,
1214 struct dx_map_entry *map_tail)
1215 {
1216 int count = 0;
1217 char *base = (char *) de;
1218 struct dx_hash_info h = *hinfo;
1219
1220 while ((char *) de < base + blocksize) {
1221 if (de->name_len && de->inode) {
1222 ext4fs_dirhash(dir, de->name, de->name_len, &h);
1223 map_tail--;
1224 map_tail->hash = h.hash;
1225 map_tail->offs = ((char *) de - base)>>2;
1226 map_tail->size = le16_to_cpu(de->rec_len);
1227 count++;
1228 cond_resched();
1229 }
1230 /* XXX: do we need to check rec_len == 0 case? -Chris */
1231 de = ext4_next_entry(de, blocksize);
1232 }
1233 return count;
1234 }
1235
1236 /* Sort map by hash value */
1237 static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1238 {
1239 struct dx_map_entry *p, *q, *top = map + count - 1;
1240 int more;
1241 /* Combsort until bubble sort doesn't suck */
1242 while (count > 2) {
1243 count = count*10/13;
1244 if (count - 9 < 2) /* 9, 10 -> 11 */
1245 count = 11;
1246 for (p = top, q = p - count; q >= map; p--, q--)
1247 if (p->hash < q->hash)
1248 swap(*p, *q);
1249 }
1250 /* Garden variety bubble sort */
1251 do {
1252 more = 0;
1253 q = top;
1254 while (q-- > map) {
1255 if (q[1].hash >= q[0].hash)
1256 continue;
1257 swap(*(q+1), *q);
1258 more = 1;
1259 }
1260 } while(more);
1261 }
1262
1263 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
1264 {
1265 struct dx_entry *entries = frame->entries;
1266 struct dx_entry *old = frame->at, *new = old + 1;
1267 int count = dx_get_count(entries);
1268
1269 assert(count < dx_get_limit(entries));
1270 assert(old < entries + count);
1271 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1272 dx_set_hash(new, hash);
1273 dx_set_block(new, block);
1274 dx_set_count(entries, count + 1);
1275 }
1276
1277 #ifdef CONFIG_UNICODE
1278 /*
1279 * Test whether a case-insensitive directory entry matches the filename
1280 * being searched for. If quick is set, assume the name being looked up
1281 * is already in the casefolded form.
1282 *
1283 * Returns: 0 if the directory entry matches, more than 0 if it
1284 * doesn't match or less than zero on error.
1285 */
1286 int ext4_ci_compare(const struct inode *parent, const struct qstr *name,
1287 const struct qstr *entry, bool quick)
1288 {
1289 const struct ext4_sb_info *sbi = EXT4_SB(parent->i_sb);
1290 const struct unicode_map *um = sbi->s_encoding;
1291 int ret;
1292
1293 if (quick)
1294 ret = utf8_strncasecmp_folded(um, name, entry);
1295 else
1296 ret = utf8_strncasecmp(um, name, entry);
1297
1298 if (ret < 0) {
1299 /* Handle invalid character sequence as either an error
1300 * or as an opaque byte sequence.
1301 */
1302 if (ext4_has_strict_mode(sbi))
1303 return -EINVAL;
1304
1305 if (name->len != entry->len)
1306 return 1;
1307
1308 return !!memcmp(name->name, entry->name, name->len);
1309 }
1310
1311 return ret;
1312 }
1313
1314 void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
1315 struct fscrypt_str *cf_name)
1316 {
1317 int len;
1318
1319 if (!IS_CASEFOLDED(dir) || !EXT4_SB(dir->i_sb)->s_encoding) {
1320 cf_name->name = NULL;
1321 return;
1322 }
1323
1324 cf_name->name = kmalloc(EXT4_NAME_LEN, GFP_NOFS);
1325 if (!cf_name->name)
1326 return;
1327
1328 len = utf8_casefold(EXT4_SB(dir->i_sb)->s_encoding,
1329 iname, cf_name->name,
1330 EXT4_NAME_LEN);
1331 if (len <= 0) {
1332 kfree(cf_name->name);
1333 cf_name->name = NULL;
1334 return;
1335 }
1336 cf_name->len = (unsigned) len;
1337
1338 }
1339 #endif
1340
1341 /*
1342 * Test whether a directory entry matches the filename being searched for.
1343 *
1344 * Return: %true if the directory entry matches, otherwise %false.
1345 */
1346 static inline bool ext4_match(const struct inode *parent,
1347 const struct ext4_filename *fname,
1348 const struct ext4_dir_entry_2 *de)
1349 {
1350 struct fscrypt_name f;
1351 #ifdef CONFIG_UNICODE
1352 const struct qstr entry = {.name = de->name, .len = de->name_len};
1353 #endif
1354
1355 if (!de->inode)
1356 return false;
1357
1358 f.usr_fname = fname->usr_fname;
1359 f.disk_name = fname->disk_name;
1360 #ifdef CONFIG_FS_ENCRYPTION
1361 f.crypto_buf = fname->crypto_buf;
1362 #endif
1363
1364 #ifdef CONFIG_UNICODE
1365 if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent)) {
1366 if (fname->cf_name.name) {
1367 struct qstr cf = {.name = fname->cf_name.name,
1368 .len = fname->cf_name.len};
1369 return !ext4_ci_compare(parent, &cf, &entry, true);
1370 }
1371 return !ext4_ci_compare(parent, fname->usr_fname, &entry,
1372 false);
1373 }
1374 #endif
1375
1376 return fscrypt_match_name(&f, de->name, de->name_len);
1377 }
1378
1379 /*
1380 * Returns 0 if not found, -1 on failure, and 1 on success
1381 */
1382 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
1383 struct inode *dir, struct ext4_filename *fname,
1384 unsigned int offset, struct ext4_dir_entry_2 **res_dir)
1385 {
1386 struct ext4_dir_entry_2 * de;
1387 char * dlimit;
1388 int de_len;
1389
1390 de = (struct ext4_dir_entry_2 *)search_buf;
1391 dlimit = search_buf + buf_size;
1392 while ((char *) de < dlimit) {
1393 /* this code is executed quadratically often */
1394 /* do minimal checking `by hand' */
1395 if ((char *) de + de->name_len <= dlimit &&
1396 ext4_match(dir, fname, de)) {
1397 /* found a match - just to be sure, do
1398 * a full check */
1399 if (ext4_check_dir_entry(dir, NULL, de, bh, search_buf,
1400 buf_size, offset))
1401 return -1;
1402 *res_dir = de;
1403 return 1;
1404 }
1405 /* prevent looping on a bad block */
1406 de_len = ext4_rec_len_from_disk(de->rec_len,
1407 dir->i_sb->s_blocksize);
1408 if (de_len <= 0)
1409 return -1;
1410 offset += de_len;
1411 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1412 }
1413 return 0;
1414 }
1415
1416 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1417 struct ext4_dir_entry *de)
1418 {
1419 struct super_block *sb = dir->i_sb;
1420
1421 if (!is_dx(dir))
1422 return 0;
1423 if (block == 0)
1424 return 1;
1425 if (de->inode == 0 &&
1426 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
1427 sb->s_blocksize)
1428 return 1;
1429 return 0;
1430 }
1431
1432 /*
1433 * __ext4_find_entry()
1434 *
1435 * finds an entry in the specified directory with the wanted name. It
1436 * returns the cache buffer in which the entry was found, and the entry
1437 * itself (as a parameter - res_dir). It does NOT read the inode of the
1438 * entry - you'll have to do that yourself if you want to.
1439 *
1440 * The returned buffer_head has ->b_count elevated. The caller is expected
1441 * to brelse() it when appropriate.
1442 */
1443 static struct buffer_head *__ext4_find_entry(struct inode *dir,
1444 struct ext4_filename *fname,
1445 struct ext4_dir_entry_2 **res_dir,
1446 int *inlined)
1447 {
1448 struct super_block *sb;
1449 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1450 struct buffer_head *bh, *ret = NULL;
1451 ext4_lblk_t start, block;
1452 const u8 *name = fname->usr_fname->name;
1453 size_t ra_max = 0; /* Number of bh's in the readahead
1454 buffer, bh_use[] */
1455 size_t ra_ptr = 0; /* Current index into readahead
1456 buffer */
1457 ext4_lblk_t nblocks;
1458 int i, namelen, retval;
1459
1460 *res_dir = NULL;
1461 sb = dir->i_sb;
1462 namelen = fname->usr_fname->len;
1463 if (namelen > EXT4_NAME_LEN)
1464 return NULL;
1465
1466 if (ext4_has_inline_data(dir)) {
1467 int has_inline_data = 1;
1468 ret = ext4_find_inline_entry(dir, fname, res_dir,
1469 &has_inline_data);
1470 if (has_inline_data) {
1471 if (inlined)
1472 *inlined = 1;
1473 goto cleanup_and_exit;
1474 }
1475 }
1476
1477 if ((namelen <= 2) && (name[0] == '.') &&
1478 (name[1] == '.' || name[1] == '\0')) {
1479 /*
1480 * "." or ".." will only be in the first block
1481 * NFS may look up ".."; "." should be handled by the VFS
1482 */
1483 block = start = 0;
1484 nblocks = 1;
1485 goto restart;
1486 }
1487 if (is_dx(dir)) {
1488 ret = ext4_dx_find_entry(dir, fname, res_dir);
1489 /*
1490 * On success, or if the error was file not found,
1491 * return. Otherwise, fall back to doing a search the
1492 * old fashioned way.
1493 */
1494 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR)
1495 goto cleanup_and_exit;
1496 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1497 "falling back\n"));
1498 ret = NULL;
1499 }
1500 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1501 if (!nblocks) {
1502 ret = NULL;
1503 goto cleanup_and_exit;
1504 }
1505 start = EXT4_I(dir)->i_dir_start_lookup;
1506 if (start >= nblocks)
1507 start = 0;
1508 block = start;
1509 restart:
1510 do {
1511 /*
1512 * We deal with the read-ahead logic here.
1513 */
1514 cond_resched();
1515 if (ra_ptr >= ra_max) {
1516 /* Refill the readahead buffer */
1517 ra_ptr = 0;
1518 if (block < start)
1519 ra_max = start - block;
1520 else
1521 ra_max = nblocks - block;
1522 ra_max = min(ra_max, ARRAY_SIZE(bh_use));
1523 retval = ext4_bread_batch(dir, block, ra_max,
1524 false /* wait */, bh_use);
1525 if (retval) {
1526 ret = ERR_PTR(retval);
1527 ra_max = 0;
1528 goto cleanup_and_exit;
1529 }
1530 }
1531 if ((bh = bh_use[ra_ptr++]) == NULL)
1532 goto next;
1533 wait_on_buffer(bh);
1534 if (!buffer_uptodate(bh)) {
1535 EXT4_ERROR_INODE_ERR(dir, EIO,
1536 "reading directory lblock %lu",
1537 (unsigned long) block);
1538 brelse(bh);
1539 ret = ERR_PTR(-EIO);
1540 goto cleanup_and_exit;
1541 }
1542 if (!buffer_verified(bh) &&
1543 !is_dx_internal_node(dir, block,
1544 (struct ext4_dir_entry *)bh->b_data) &&
1545 !ext4_dirblock_csum_verify(dir, bh)) {
1546 EXT4_ERROR_INODE_ERR(dir, EFSBADCRC,
1547 "checksumming directory "
1548 "block %lu", (unsigned long)block);
1549 brelse(bh);
1550 ret = ERR_PTR(-EFSBADCRC);
1551 goto cleanup_and_exit;
1552 }
1553 set_buffer_verified(bh);
1554 i = search_dirblock(bh, dir, fname,
1555 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
1556 if (i == 1) {
1557 EXT4_I(dir)->i_dir_start_lookup = block;
1558 ret = bh;
1559 goto cleanup_and_exit;
1560 } else {
1561 brelse(bh);
1562 if (i < 0)
1563 goto cleanup_and_exit;
1564 }
1565 next:
1566 if (++block >= nblocks)
1567 block = 0;
1568 } while (block != start);
1569
1570 /*
1571 * If the directory has grown while we were searching, then
1572 * search the last part of the directory before giving up.
1573 */
1574 block = nblocks;
1575 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1576 if (block < nblocks) {
1577 start = 0;
1578 goto restart;
1579 }
1580
1581 cleanup_and_exit:
1582 /* Clean up the read-ahead blocks */
1583 for (; ra_ptr < ra_max; ra_ptr++)
1584 brelse(bh_use[ra_ptr]);
1585 return ret;
1586 }
1587
1588 static struct buffer_head *ext4_find_entry(struct inode *dir,
1589 const struct qstr *d_name,
1590 struct ext4_dir_entry_2 **res_dir,
1591 int *inlined)
1592 {
1593 int err;
1594 struct ext4_filename fname;
1595 struct buffer_head *bh;
1596
1597 err = ext4_fname_setup_filename(dir, d_name, 1, &fname);
1598 if (err == -ENOENT)
1599 return NULL;
1600 if (err)
1601 return ERR_PTR(err);
1602
1603 bh = __ext4_find_entry(dir, &fname, res_dir, inlined);
1604
1605 ext4_fname_free_filename(&fname);
1606 return bh;
1607 }
1608
1609 static struct buffer_head *ext4_lookup_entry(struct inode *dir,
1610 struct dentry *dentry,
1611 struct ext4_dir_entry_2 **res_dir)
1612 {
1613 int err;
1614 struct ext4_filename fname;
1615 struct buffer_head *bh;
1616
1617 err = ext4_fname_prepare_lookup(dir, dentry, &fname);
1618 if (err == -ENOENT)
1619 return NULL;
1620 if (err)
1621 return ERR_PTR(err);
1622
1623 bh = __ext4_find_entry(dir, &fname, res_dir, NULL);
1624
1625 ext4_fname_free_filename(&fname);
1626 return bh;
1627 }
1628
1629 static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
1630 struct ext4_filename *fname,
1631 struct ext4_dir_entry_2 **res_dir)
1632 {
1633 struct super_block * sb = dir->i_sb;
1634 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1635 struct buffer_head *bh;
1636 ext4_lblk_t block;
1637 int retval;
1638
1639 #ifdef CONFIG_FS_ENCRYPTION
1640 *res_dir = NULL;
1641 #endif
1642 frame = dx_probe(fname, dir, NULL, frames);
1643 if (IS_ERR(frame))
1644 return (struct buffer_head *) frame;
1645 do {
1646 block = dx_get_block(frame->at);
1647 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
1648 if (IS_ERR(bh))
1649 goto errout;
1650
1651 retval = search_dirblock(bh, dir, fname,
1652 block << EXT4_BLOCK_SIZE_BITS(sb),
1653 res_dir);
1654 if (retval == 1)
1655 goto success;
1656 brelse(bh);
1657 if (retval == -1) {
1658 bh = ERR_PTR(ERR_BAD_DX_DIR);
1659 goto errout;
1660 }
1661
1662 /* Check to see if we should continue to search */
1663 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame,
1664 frames, NULL);
1665 if (retval < 0) {
1666 ext4_warning_inode(dir,
1667 "error %d reading directory index block",
1668 retval);
1669 bh = ERR_PTR(retval);
1670 goto errout;
1671 }
1672 } while (retval == 1);
1673
1674 bh = NULL;
1675 errout:
1676 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name));
1677 success:
1678 dx_release(frames);
1679 return bh;
1680 }
1681
1682 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
1683 {
1684 struct inode *inode;
1685 struct ext4_dir_entry_2 *de;
1686 struct buffer_head *bh;
1687
1688 if (dentry->d_name.len > EXT4_NAME_LEN)
1689 return ERR_PTR(-ENAMETOOLONG);
1690
1691 bh = ext4_lookup_entry(dir, dentry, &de);
1692 if (IS_ERR(bh))
1693 return ERR_CAST(bh);
1694 inode = NULL;
1695 if (bh) {
1696 __u32 ino = le32_to_cpu(de->inode);
1697 brelse(bh);
1698 if (!ext4_valid_inum(dir->i_sb, ino)) {
1699 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1700 return ERR_PTR(-EFSCORRUPTED);
1701 }
1702 if (unlikely(ino == dir->i_ino)) {
1703 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
1704 dentry);
1705 return ERR_PTR(-EFSCORRUPTED);
1706 }
1707 inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL);
1708 if (inode == ERR_PTR(-ESTALE)) {
1709 EXT4_ERROR_INODE(dir,
1710 "deleted inode referenced: %u",
1711 ino);
1712 return ERR_PTR(-EFSCORRUPTED);
1713 }
1714 if (!IS_ERR(inode) && IS_ENCRYPTED(dir) &&
1715 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
1716 !fscrypt_has_permitted_context(dir, inode)) {
1717 ext4_warning(inode->i_sb,
1718 "Inconsistent encryption contexts: %lu/%lu",
1719 dir->i_ino, inode->i_ino);
1720 iput(inode);
1721 return ERR_PTR(-EPERM);
1722 }
1723 }
1724
1725 #ifdef CONFIG_UNICODE
1726 if (!inode && IS_CASEFOLDED(dir)) {
1727 /* Eventually we want to call d_add_ci(dentry, NULL)
1728 * for negative dentries in the encoding case as
1729 * well. For now, prevent the negative dentry
1730 * from being cached.
1731 */
1732 return NULL;
1733 }
1734 #endif
1735 return d_splice_alias(inode, dentry);
1736 }
1737
1738
1739 struct dentry *ext4_get_parent(struct dentry *child)
1740 {
1741 __u32 ino;
1742 static const struct qstr dotdot = QSTR_INIT("..", 2);
1743 struct ext4_dir_entry_2 * de;
1744 struct buffer_head *bh;
1745
1746 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL);
1747 if (IS_ERR(bh))
1748 return ERR_CAST(bh);
1749 if (!bh)
1750 return ERR_PTR(-ENOENT);
1751 ino = le32_to_cpu(de->inode);
1752 brelse(bh);
1753
1754 if (!ext4_valid_inum(child->d_sb, ino)) {
1755 EXT4_ERROR_INODE(d_inode(child),
1756 "bad parent inode number: %u", ino);
1757 return ERR_PTR(-EFSCORRUPTED);
1758 }
1759
1760 return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL));
1761 }
1762
1763 /*
1764 * Move count entries from end of map between two memory locations.
1765 * Returns pointer to last entry moved.
1766 */
1767 static struct ext4_dir_entry_2 *
1768 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1769 unsigned blocksize)
1770 {
1771 unsigned rec_len = 0;
1772
1773 while (count--) {
1774 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
1775 (from + (map->offs<<2));
1776 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1777 memcpy (to, de, rec_len);
1778 ((struct ext4_dir_entry_2 *) to)->rec_len =
1779 ext4_rec_len_to_disk(rec_len, blocksize);
1780 de->inode = 0;
1781 map++;
1782 to += rec_len;
1783 }
1784 return (struct ext4_dir_entry_2 *) (to - rec_len);
1785 }
1786
1787 /*
1788 * Compact each dir entry in the range to the minimal rec_len.
1789 * Returns pointer to last entry in range.
1790 */
1791 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
1792 {
1793 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
1794 unsigned rec_len = 0;
1795
1796 prev = to = de;
1797 while ((char*)de < base + blocksize) {
1798 next = ext4_next_entry(de, blocksize);
1799 if (de->inode && de->name_len) {
1800 rec_len = EXT4_DIR_REC_LEN(de->name_len);
1801 if (de > to)
1802 memmove(to, de, rec_len);
1803 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
1804 prev = to;
1805 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
1806 }
1807 de = next;
1808 }
1809 return prev;
1810 }
1811
1812 /*
1813 * Split a full leaf block to make room for a new dir entry.
1814 * Allocate a new block, and move entries so that they are approx. equally full.
1815 * Returns pointer to de in block into which the new entry will be inserted.
1816 */
1817 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1818 struct buffer_head **bh,struct dx_frame *frame,
1819 struct dx_hash_info *hinfo)
1820 {
1821 unsigned blocksize = dir->i_sb->s_blocksize;
1822 unsigned count, continued;
1823 struct buffer_head *bh2;
1824 ext4_lblk_t newblock;
1825 u32 hash2;
1826 struct dx_map_entry *map;
1827 char *data1 = (*bh)->b_data, *data2;
1828 unsigned split, move, size;
1829 struct ext4_dir_entry_2 *de = NULL, *de2;
1830 int csum_size = 0;
1831 int err = 0, i;
1832
1833 if (ext4_has_metadata_csum(dir->i_sb))
1834 csum_size = sizeof(struct ext4_dir_entry_tail);
1835
1836 bh2 = ext4_append(handle, dir, &newblock);
1837 if (IS_ERR(bh2)) {
1838 brelse(*bh);
1839 *bh = NULL;
1840 return (struct ext4_dir_entry_2 *) bh2;
1841 }
1842
1843 BUFFER_TRACE(*bh, "get_write_access");
1844 err = ext4_journal_get_write_access(handle, *bh);
1845 if (err)
1846 goto journal_error;
1847
1848 BUFFER_TRACE(frame->bh, "get_write_access");
1849 err = ext4_journal_get_write_access(handle, frame->bh);
1850 if (err)
1851 goto journal_error;
1852
1853 data2 = bh2->b_data;
1854
1855 /* create map in the end of data2 block */
1856 map = (struct dx_map_entry *) (data2 + blocksize);
1857 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1,
1858 blocksize, hinfo, map);
1859 map -= count;
1860 dx_sort_map(map, count);
1861 /* Ensure that neither split block is over half full */
1862 size = 0;
1863 move = 0;
1864 for (i = count-1; i >= 0; i--) {
1865 /* is more than half of this entry in 2nd half of the block? */
1866 if (size + map[i].size/2 > blocksize/2)
1867 break;
1868 size += map[i].size;
1869 move++;
1870 }
1871 /*
1872 * map index at which we will split
1873 *
1874 * If the sum of active entries didn't exceed half the block size, just
1875 * split it in half by count; each resulting block will have at least
1876 * half the space free.
1877 */
1878 if (i > 0)
1879 split = count - move;
1880 else
1881 split = count/2;
1882
1883 hash2 = map[split].hash;
1884 continued = hash2 == map[split - 1].hash;
1885 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1886 (unsigned long)dx_get_block(frame->at),
1887 hash2, split, count-split));
1888
1889 /* Fancy dance to stay within two buffers */
1890 de2 = dx_move_dirents(data1, data2, map + split, count - split,
1891 blocksize);
1892 de = dx_pack_dirents(data1, blocksize);
1893 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1894 (char *) de,
1895 blocksize);
1896 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1897 (char *) de2,
1898 blocksize);
1899 if (csum_size) {
1900 ext4_initialize_dirent_tail(*bh, blocksize);
1901 ext4_initialize_dirent_tail(bh2, blocksize);
1902 }
1903
1904 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
1905 blocksize, 1));
1906 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,
1907 blocksize, 1));
1908
1909 /* Which block gets the new entry? */
1910 if (hinfo->hash >= hash2) {
1911 swap(*bh, bh2);
1912 de = de2;
1913 }
1914 dx_insert_block(frame, hash2 + continued, newblock);
1915 err = ext4_handle_dirty_dirblock(handle, dir, bh2);
1916 if (err)
1917 goto journal_error;
1918 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1919 if (err)
1920 goto journal_error;
1921 brelse(bh2);
1922 dxtrace(dx_show_index("frame", frame->entries));
1923 return de;
1924
1925 journal_error:
1926 brelse(*bh);
1927 brelse(bh2);
1928 *bh = NULL;
1929 ext4_std_error(dir->i_sb, err);
1930 return ERR_PTR(err);
1931 }
1932
1933 int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1934 struct buffer_head *bh,
1935 void *buf, int buf_size,
1936 struct ext4_filename *fname,
1937 struct ext4_dir_entry_2 **dest_de)
1938 {
1939 struct ext4_dir_entry_2 *de;
1940 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname));
1941 int nlen, rlen;
1942 unsigned int offset = 0;
1943 char *top;
1944
1945 de = (struct ext4_dir_entry_2 *)buf;
1946 top = buf + buf_size - reclen;
1947 while ((char *) de <= top) {
1948 if (ext4_check_dir_entry(dir, NULL, de, bh,
1949 buf, buf_size, offset))
1950 return -EFSCORRUPTED;
1951 if (ext4_match(dir, fname, de))
1952 return -EEXIST;
1953 nlen = EXT4_DIR_REC_LEN(de->name_len);
1954 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1955 if ((de->inode ? rlen - nlen : rlen) >= reclen)
1956 break;
1957 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1958 offset += rlen;
1959 }
1960 if ((char *) de > top)
1961 return -ENOSPC;
1962
1963 *dest_de = de;
1964 return 0;
1965 }
1966
1967 void ext4_insert_dentry(struct inode *inode,
1968 struct ext4_dir_entry_2 *de,
1969 int buf_size,
1970 struct ext4_filename *fname)
1971 {
1972
1973 int nlen, rlen;
1974
1975 nlen = EXT4_DIR_REC_LEN(de->name_len);
1976 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1977 if (de->inode) {
1978 struct ext4_dir_entry_2 *de1 =
1979 (struct ext4_dir_entry_2 *)((char *)de + nlen);
1980 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
1981 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
1982 de = de1;
1983 }
1984 de->file_type = EXT4_FT_UNKNOWN;
1985 de->inode = cpu_to_le32(inode->i_ino);
1986 ext4_set_de_type(inode->i_sb, de, inode->i_mode);
1987 de->name_len = fname_len(fname);
1988 memcpy(de->name, fname_name(fname), fname_len(fname));
1989 }
1990
1991 /*
1992 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1993 * it points to a directory entry which is guaranteed to be large
1994 * enough for new directory entry. If de is NULL, then
1995 * add_dirent_to_buf will attempt search the directory block for
1996 * space. It will return -ENOSPC if no space is available, and -EIO
1997 * and -EEXIST if directory entry already exists.
1998 */
1999 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
2000 struct inode *dir,
2001 struct inode *inode, struct ext4_dir_entry_2 *de,
2002 struct buffer_head *bh)
2003 {
2004 unsigned int blocksize = dir->i_sb->s_blocksize;
2005 int csum_size = 0;
2006 int err, err2;
2007
2008 if (ext4_has_metadata_csum(inode->i_sb))
2009 csum_size = sizeof(struct ext4_dir_entry_tail);
2010
2011 if (!de) {
2012 err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
2013 blocksize - csum_size, fname, &de);
2014 if (err)
2015 return err;
2016 }
2017 BUFFER_TRACE(bh, "get_write_access");
2018 err = ext4_journal_get_write_access(handle, bh);
2019 if (err) {
2020 ext4_std_error(dir->i_sb, err);
2021 return err;
2022 }
2023
2024 /* By now the buffer is marked for journaling */
2025 ext4_insert_dentry(inode, de, blocksize, fname);
2026
2027 /*
2028 * XXX shouldn't update any times until successful
2029 * completion of syscall, but too many callers depend
2030 * on this.
2031 *
2032 * XXX similarly, too many callers depend on
2033 * ext4_new_inode() setting the times, but error
2034 * recovery deletes the inode, so the worst that can
2035 * happen is that the times are slightly out of date
2036 * and/or different from the directory change time.
2037 */
2038 dir->i_mtime = dir->i_ctime = current_time(dir);
2039 ext4_update_dx_flag(dir);
2040 inode_inc_iversion(dir);
2041 err2 = ext4_mark_inode_dirty(handle, dir);
2042 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2043 err = ext4_handle_dirty_dirblock(handle, dir, bh);
2044 if (err)
2045 ext4_std_error(dir->i_sb, err);
2046 return err ? err : err2;
2047 }
2048
2049 /*
2050 * This converts a one block unindexed directory to a 3 block indexed
2051 * directory, and adds the dentry to the indexed directory.
2052 */
2053 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
2054 struct inode *dir,
2055 struct inode *inode, struct buffer_head *bh)
2056 {
2057 struct buffer_head *bh2;
2058 struct dx_root *root;
2059 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2060 struct dx_entry *entries;
2061 struct ext4_dir_entry_2 *de, *de2;
2062 char *data2, *top;
2063 unsigned len;
2064 int retval;
2065 unsigned blocksize;
2066 ext4_lblk_t block;
2067 struct fake_dirent *fde;
2068 int csum_size = 0;
2069
2070 if (ext4_has_metadata_csum(inode->i_sb))
2071 csum_size = sizeof(struct ext4_dir_entry_tail);
2072
2073 blocksize = dir->i_sb->s_blocksize;
2074 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
2075 BUFFER_TRACE(bh, "get_write_access");
2076 retval = ext4_journal_get_write_access(handle, bh);
2077 if (retval) {
2078 ext4_std_error(dir->i_sb, retval);
2079 brelse(bh);
2080 return retval;
2081 }
2082 root = (struct dx_root *) bh->b_data;
2083
2084 /* The 0th block becomes the root, move the dirents out */
2085 fde = &root->dotdot;
2086 de = (struct ext4_dir_entry_2 *)((char *)fde +
2087 ext4_rec_len_from_disk(fde->rec_len, blocksize));
2088 if ((char *) de >= (((char *) root) + blocksize)) {
2089 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
2090 brelse(bh);
2091 return -EFSCORRUPTED;
2092 }
2093 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
2094
2095 /* Allocate new block for the 0th block's dirents */
2096 bh2 = ext4_append(handle, dir, &block);
2097 if (IS_ERR(bh2)) {
2098 brelse(bh);
2099 return PTR_ERR(bh2);
2100 }
2101 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
2102 data2 = bh2->b_data;
2103
2104 memcpy(data2, de, len);
2105 de = (struct ext4_dir_entry_2 *) data2;
2106 top = data2 + len;
2107 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
2108 de = de2;
2109 de->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
2110 (char *) de, blocksize);
2111
2112 if (csum_size)
2113 ext4_initialize_dirent_tail(bh2, blocksize);
2114
2115 /* Initialize the root; the dot dirents already exist */
2116 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
2117 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
2118 blocksize);
2119 memset (&root->info, 0, sizeof(root->info));
2120 root->info.info_length = sizeof(root->info);
2121 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
2122 entries = root->entries;
2123 dx_set_block(entries, 1);
2124 dx_set_count(entries, 1);
2125 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
2126
2127 /* Initialize as for dx_probe */
2128 fname->hinfo.hash_version = root->info.hash_version;
2129 if (fname->hinfo.hash_version <= DX_HASH_TEA)
2130 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
2131 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
2132 ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), &fname->hinfo);
2133
2134 memset(frames, 0, sizeof(frames));
2135 frame = frames;
2136 frame->entries = entries;
2137 frame->at = entries;
2138 frame->bh = bh;
2139
2140 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
2141 if (retval)
2142 goto out_frames;
2143 retval = ext4_handle_dirty_dirblock(handle, dir, bh2);
2144 if (retval)
2145 goto out_frames;
2146
2147 de = do_split(handle,dir, &bh2, frame, &fname->hinfo);
2148 if (IS_ERR(de)) {
2149 retval = PTR_ERR(de);
2150 goto out_frames;
2151 }
2152
2153 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2);
2154 out_frames:
2155 /*
2156 * Even if the block split failed, we have to properly write
2157 * out all the changes we did so far. Otherwise we can end up
2158 * with corrupted filesystem.
2159 */
2160 if (retval)
2161 ext4_mark_inode_dirty(handle, dir);
2162 dx_release(frames);
2163 brelse(bh2);
2164 return retval;
2165 }
2166
2167 /*
2168 * ext4_add_entry()
2169 *
2170 * adds a file entry to the specified directory, using the same
2171 * semantics as ext4_find_entry(). It returns NULL if it failed.
2172 *
2173 * NOTE!! The inode part of 'de' is left at 0 - which means you
2174 * may not sleep between calling this and putting something into
2175 * the entry, as someone else might have used it while you slept.
2176 */
2177 static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
2178 struct inode *inode)
2179 {
2180 struct inode *dir = d_inode(dentry->d_parent);
2181 struct buffer_head *bh = NULL;
2182 struct ext4_dir_entry_2 *de;
2183 struct super_block *sb;
2184 #ifdef CONFIG_UNICODE
2185 struct ext4_sb_info *sbi;
2186 #endif
2187 struct ext4_filename fname;
2188 int retval;
2189 int dx_fallback=0;
2190 unsigned blocksize;
2191 ext4_lblk_t block, blocks;
2192 int csum_size = 0;
2193
2194 if (ext4_has_metadata_csum(inode->i_sb))
2195 csum_size = sizeof(struct ext4_dir_entry_tail);
2196
2197 sb = dir->i_sb;
2198 blocksize = sb->s_blocksize;
2199 if (!dentry->d_name.len)
2200 return -EINVAL;
2201
2202 #ifdef CONFIG_UNICODE
2203 sbi = EXT4_SB(sb);
2204 if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) &&
2205 sbi->s_encoding && utf8_validate(sbi->s_encoding, &dentry->d_name))
2206 return -EINVAL;
2207 #endif
2208
2209 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);
2210 if (retval)
2211 return retval;
2212
2213 if (ext4_has_inline_data(dir)) {
2214 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode);
2215 if (retval < 0)
2216 goto out;
2217 if (retval == 1) {
2218 retval = 0;
2219 goto out;
2220 }
2221 }
2222
2223 if (is_dx(dir)) {
2224 retval = ext4_dx_add_entry(handle, &fname, dir, inode);
2225 if (!retval || (retval != ERR_BAD_DX_DIR))
2226 goto out;
2227 /* Can we just ignore htree data? */
2228 if (ext4_has_metadata_csum(sb)) {
2229 EXT4_ERROR_INODE(dir,
2230 "Directory has corrupted htree index.");
2231 retval = -EFSCORRUPTED;
2232 goto out;
2233 }
2234 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
2235 dx_fallback++;
2236 retval = ext4_mark_inode_dirty(handle, dir);
2237 if (unlikely(retval))
2238 goto out;
2239 }
2240 blocks = dir->i_size >> sb->s_blocksize_bits;
2241 for (block = 0; block < blocks; block++) {
2242 bh = ext4_read_dirblock(dir, block, DIRENT);
2243 if (bh == NULL) {
2244 bh = ext4_bread(handle, dir, block,
2245 EXT4_GET_BLOCKS_CREATE);
2246 goto add_to_new_block;
2247 }
2248 if (IS_ERR(bh)) {
2249 retval = PTR_ERR(bh);
2250 bh = NULL;
2251 goto out;
2252 }
2253 retval = add_dirent_to_buf(handle, &fname, dir, inode,
2254 NULL, bh);
2255 if (retval != -ENOSPC)
2256 goto out;
2257
2258 if (blocks == 1 && !dx_fallback &&
2259 ext4_has_feature_dir_index(sb)) {
2260 retval = make_indexed_dir(handle, &fname, dir,
2261 inode, bh);
2262 bh = NULL; /* make_indexed_dir releases bh */
2263 goto out;
2264 }
2265 brelse(bh);
2266 }
2267 bh = ext4_append(handle, dir, &block);
2268 add_to_new_block:
2269 if (IS_ERR(bh)) {
2270 retval = PTR_ERR(bh);
2271 bh = NULL;
2272 goto out;
2273 }
2274 de = (struct ext4_dir_entry_2 *) bh->b_data;
2275 de->inode = 0;
2276 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
2277
2278 if (csum_size)
2279 ext4_initialize_dirent_tail(bh, blocksize);
2280
2281 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);
2282 out:
2283 ext4_fname_free_filename(&fname);
2284 brelse(bh);
2285 if (retval == 0)
2286 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
2287 return retval;
2288 }
2289
2290 /*
2291 * Returns 0 for success, or a negative error value
2292 */
2293 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
2294 struct inode *dir, struct inode *inode)
2295 {
2296 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2297 struct dx_entry *entries, *at;
2298 struct buffer_head *bh;
2299 struct super_block *sb = dir->i_sb;
2300 struct ext4_dir_entry_2 *de;
2301 int restart;
2302 int err;
2303
2304 again:
2305 restart = 0;
2306 frame = dx_probe(fname, dir, NULL, frames);
2307 if (IS_ERR(frame))
2308 return PTR_ERR(frame);
2309 entries = frame->entries;
2310 at = frame->at;
2311 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT_HTREE);
2312 if (IS_ERR(bh)) {
2313 err = PTR_ERR(bh);
2314 bh = NULL;
2315 goto cleanup;
2316 }
2317
2318 BUFFER_TRACE(bh, "get_write_access");
2319 err = ext4_journal_get_write_access(handle, bh);
2320 if (err)
2321 goto journal_error;
2322
2323 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh);
2324 if (err != -ENOSPC)
2325 goto cleanup;
2326
2327 err = 0;
2328 /* Block full, should compress but for now just split */
2329 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
2330 dx_get_count(entries), dx_get_limit(entries)));
2331 /* Need to split index? */
2332 if (dx_get_count(entries) == dx_get_limit(entries)) {
2333 ext4_lblk_t newblock;
2334 int levels = frame - frames + 1;
2335 unsigned int icount;
2336 int add_level = 1;
2337 struct dx_entry *entries2;
2338 struct dx_node *node2;
2339 struct buffer_head *bh2;
2340
2341 while (frame > frames) {
2342 if (dx_get_count((frame - 1)->entries) <
2343 dx_get_limit((frame - 1)->entries)) {
2344 add_level = 0;
2345 break;
2346 }
2347 frame--; /* split higher index block */
2348 at = frame->at;
2349 entries = frame->entries;
2350 restart = 1;
2351 }
2352 if (add_level && levels == ext4_dir_htree_level(sb)) {
2353 ext4_warning(sb, "Directory (ino: %lu) index full, "
2354 "reach max htree level :%d",
2355 dir->i_ino, levels);
2356 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) {
2357 ext4_warning(sb, "Large directory feature is "
2358 "not enabled on this "
2359 "filesystem");
2360 }
2361 err = -ENOSPC;
2362 goto cleanup;
2363 }
2364 icount = dx_get_count(entries);
2365 bh2 = ext4_append(handle, dir, &newblock);
2366 if (IS_ERR(bh2)) {
2367 err = PTR_ERR(bh2);
2368 goto cleanup;
2369 }
2370 node2 = (struct dx_node *)(bh2->b_data);
2371 entries2 = node2->entries;
2372 memset(&node2->fake, 0, sizeof(struct fake_dirent));
2373 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
2374 sb->s_blocksize);
2375 BUFFER_TRACE(frame->bh, "get_write_access");
2376 err = ext4_journal_get_write_access(handle, frame->bh);
2377 if (err)
2378 goto journal_error;
2379 if (!add_level) {
2380 unsigned icount1 = icount/2, icount2 = icount - icount1;
2381 unsigned hash2 = dx_get_hash(entries + icount1);
2382 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2383 icount1, icount2));
2384
2385 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
2386 err = ext4_journal_get_write_access(handle,
2387 (frame - 1)->bh);
2388 if (err)
2389 goto journal_error;
2390
2391 memcpy((char *) entries2, (char *) (entries + icount1),
2392 icount2 * sizeof(struct dx_entry));
2393 dx_set_count(entries, icount1);
2394 dx_set_count(entries2, icount2);
2395 dx_set_limit(entries2, dx_node_limit(dir));
2396
2397 /* Which index block gets the new entry? */
2398 if (at - entries >= icount1) {
2399 frame->at = at = at - entries - icount1 + entries2;
2400 frame->entries = entries = entries2;
2401 swap(frame->bh, bh2);
2402 }
2403 dx_insert_block((frame - 1), hash2, newblock);
2404 dxtrace(dx_show_index("node", frame->entries));
2405 dxtrace(dx_show_index("node",
2406 ((struct dx_node *) bh2->b_data)->entries));
2407 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2408 if (err)
2409 goto journal_error;
2410 brelse (bh2);
2411 err = ext4_handle_dirty_dx_node(handle, dir,
2412 (frame - 1)->bh);
2413 if (err)
2414 goto journal_error;
2415 if (restart) {
2416 err = ext4_handle_dirty_dx_node(handle, dir,
2417 frame->bh);
2418 goto journal_error;
2419 }
2420 } else {
2421 struct dx_root *dxroot;
2422 memcpy((char *) entries2, (char *) entries,
2423 icount * sizeof(struct dx_entry));
2424 dx_set_limit(entries2, dx_node_limit(dir));
2425
2426 /* Set up root */
2427 dx_set_count(entries, 1);
2428 dx_set_block(entries + 0, newblock);
2429 dxroot = (struct dx_root *)frames[0].bh->b_data;
2430 dxroot->info.indirect_levels += 1;
2431 dxtrace(printk(KERN_DEBUG
2432 "Creating %d level index...\n",
2433 dxroot->info.indirect_levels));
2434 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
2435 if (err)
2436 goto journal_error;
2437 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2438 brelse(bh2);
2439 restart = 1;
2440 goto journal_error;
2441 }
2442 }
2443 de = do_split(handle, dir, &bh, frame, &fname->hinfo);
2444 if (IS_ERR(de)) {
2445 err = PTR_ERR(de);
2446 goto cleanup;
2447 }
2448 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh);
2449 goto cleanup;
2450
2451 journal_error:
2452 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */
2453 cleanup:
2454 brelse(bh);
2455 dx_release(frames);
2456 /* @restart is true means htree-path has been changed, we need to
2457 * repeat dx_probe() to find out valid htree-path
2458 */
2459 if (restart && err == 0)
2460 goto again;
2461 return err;
2462 }
2463
2464 /*
2465 * ext4_generic_delete_entry deletes a directory entry by merging it
2466 * with the previous entry
2467 */
2468 int ext4_generic_delete_entry(struct inode *dir,
2469 struct ext4_dir_entry_2 *de_del,
2470 struct buffer_head *bh,
2471 void *entry_buf,
2472 int buf_size,
2473 int csum_size)
2474 {
2475 struct ext4_dir_entry_2 *de, *pde;
2476 unsigned int blocksize = dir->i_sb->s_blocksize;
2477 int i;
2478
2479 i = 0;
2480 pde = NULL;
2481 de = (struct ext4_dir_entry_2 *)entry_buf;
2482 while (i < buf_size - csum_size) {
2483 if (ext4_check_dir_entry(dir, NULL, de, bh,
2484 entry_buf, buf_size, i))
2485 return -EFSCORRUPTED;
2486 if (de == de_del) {
2487 if (pde)
2488 pde->rec_len = ext4_rec_len_to_disk(
2489 ext4_rec_len_from_disk(pde->rec_len,
2490 blocksize) +
2491 ext4_rec_len_from_disk(de->rec_len,
2492 blocksize),
2493 blocksize);
2494 else
2495 de->inode = 0;
2496 inode_inc_iversion(dir);
2497 return 0;
2498 }
2499 i += ext4_rec_len_from_disk(de->rec_len, blocksize);
2500 pde = de;
2501 de = ext4_next_entry(de, blocksize);
2502 }
2503 return -ENOENT;
2504 }
2505
2506 static int ext4_delete_entry(handle_t *handle,
2507 struct inode *dir,
2508 struct ext4_dir_entry_2 *de_del,
2509 struct buffer_head *bh)
2510 {
2511 int err, csum_size = 0;
2512
2513 if (ext4_has_inline_data(dir)) {
2514 int has_inline_data = 1;
2515 err = ext4_delete_inline_entry(handle, dir, de_del, bh,
2516 &has_inline_data);
2517 if (has_inline_data)
2518 return err;
2519 }
2520
2521 if (ext4_has_metadata_csum(dir->i_sb))
2522 csum_size = sizeof(struct ext4_dir_entry_tail);
2523
2524 BUFFER_TRACE(bh, "get_write_access");
2525 err = ext4_journal_get_write_access(handle, bh);
2526 if (unlikely(err))
2527 goto out;
2528
2529 err = ext4_generic_delete_entry(dir, de_del, bh, bh->b_data,
2530 dir->i_sb->s_blocksize, csum_size);
2531 if (err)
2532 goto out;
2533
2534 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2535 err = ext4_handle_dirty_dirblock(handle, dir, bh);
2536 if (unlikely(err))
2537 goto out;
2538
2539 return 0;
2540 out:
2541 if (err != -ENOENT)
2542 ext4_std_error(dir->i_sb, err);
2543 return err;
2544 }
2545
2546 /*
2547 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2
2548 * since this indicates that nlinks count was previously 1 to avoid overflowing
2549 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean
2550 * that subdirectory link counts are not being maintained accurately.
2551 *
2552 * The caller has already checked for i_nlink overflow in case the DIR_LINK
2553 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy
2554 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set
2555 * on regular files) and to avoid creating huge/slow non-HTREE directories.
2556 */
2557 static void ext4_inc_count(handle_t *handle, struct inode *inode)
2558 {
2559 inc_nlink(inode);
2560 if (is_dx(inode) &&
2561 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))
2562 set_nlink(inode, 1);
2563 }
2564
2565 /*
2566 * If a directory had nlink == 1, then we should let it be 1. This indicates
2567 * directory has >EXT4_LINK_MAX subdirs.
2568 */
2569 static void ext4_dec_count(handle_t *handle, struct inode *inode)
2570 {
2571 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2572 drop_nlink(inode);
2573 }
2574
2575
2576 /*
2577 * Add non-directory inode to a directory. On success, the inode reference is
2578 * consumed by dentry is instantiation. This is also indicated by clearing of
2579 * *inodep pointer. On failure, the caller is responsible for dropping the
2580 * inode reference in the safe context.
2581 */
2582 static int ext4_add_nondir(handle_t *handle,
2583 struct dentry *dentry, struct inode **inodep)
2584 {
2585 struct inode *dir = d_inode(dentry->d_parent);
2586 struct inode *inode = *inodep;
2587 int err = ext4_add_entry(handle, dentry, inode);
2588 if (!err) {
2589 err = ext4_mark_inode_dirty(handle, inode);
2590 if (IS_DIRSYNC(dir))
2591 ext4_handle_sync(handle);
2592 d_instantiate_new(dentry, inode);
2593 *inodep = NULL;
2594 return err;
2595 }
2596 drop_nlink(inode);
2597 ext4_orphan_add(handle, inode);
2598 unlock_new_inode(inode);
2599 return err;
2600 }
2601
2602 /*
2603 * By the time this is called, we already have created
2604 * the directory cache entry for the new file, but it
2605 * is so far negative - it has no inode.
2606 *
2607 * If the create succeeds, we fill in the inode information
2608 * with d_instantiate().
2609 */
2610 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
2611 bool excl)
2612 {
2613 handle_t *handle;
2614 struct inode *inode;
2615 int err, credits, retries = 0;
2616
2617 err = dquot_initialize(dir);
2618 if (err)
2619 return err;
2620
2621 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2622 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2623 retry:
2624 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2625 NULL, EXT4_HT_DIR, credits);
2626 handle = ext4_journal_current_handle();
2627 err = PTR_ERR(inode);
2628 if (!IS_ERR(inode)) {
2629 inode->i_op = &ext4_file_inode_operations;
2630 inode->i_fop = &ext4_file_operations;
2631 ext4_set_aops(inode);
2632 err = ext4_add_nondir(handle, dentry, &inode);
2633 }
2634 if (handle)
2635 ext4_journal_stop(handle);
2636 if (!IS_ERR_OR_NULL(inode))
2637 iput(inode);
2638 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2639 goto retry;
2640 return err;
2641 }
2642
2643 static int ext4_mknod(struct inode *dir, struct dentry *dentry,
2644 umode_t mode, dev_t rdev)
2645 {
2646 handle_t *handle;
2647 struct inode *inode;
2648 int err, credits, retries = 0;
2649
2650 err = dquot_initialize(dir);
2651 if (err)
2652 return err;
2653
2654 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2655 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2656 retry:
2657 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2658 NULL, EXT4_HT_DIR, credits);
2659 handle = ext4_journal_current_handle();
2660 err = PTR_ERR(inode);
2661 if (!IS_ERR(inode)) {
2662 init_special_inode(inode, inode->i_mode, rdev);
2663 inode->i_op = &ext4_special_inode_operations;
2664 err = ext4_add_nondir(handle, dentry, &inode);
2665 }
2666 if (handle)
2667 ext4_journal_stop(handle);
2668 if (!IS_ERR_OR_NULL(inode))
2669 iput(inode);
2670 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2671 goto retry;
2672 return err;
2673 }
2674
2675 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
2676 {
2677 handle_t *handle;
2678 struct inode *inode;
2679 int err, retries = 0;
2680
2681 err = dquot_initialize(dir);
2682 if (err)
2683 return err;
2684
2685 retry:
2686 inode = ext4_new_inode_start_handle(dir, mode,
2687 NULL, 0, NULL,
2688 EXT4_HT_DIR,
2689 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2690 4 + EXT4_XATTR_TRANS_BLOCKS);
2691 handle = ext4_journal_current_handle();
2692 err = PTR_ERR(inode);
2693 if (!IS_ERR(inode)) {
2694 inode->i_op = &ext4_file_inode_operations;
2695 inode->i_fop = &ext4_file_operations;
2696 ext4_set_aops(inode);
2697 d_tmpfile(dentry, inode);
2698 err = ext4_orphan_add(handle, inode);
2699 if (err)
2700 goto err_unlock_inode;
2701 mark_inode_dirty(inode);
2702 unlock_new_inode(inode);
2703 }
2704 if (handle)
2705 ext4_journal_stop(handle);
2706 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2707 goto retry;
2708 return err;
2709 err_unlock_inode:
2710 ext4_journal_stop(handle);
2711 unlock_new_inode(inode);
2712 return err;
2713 }
2714
2715 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2716 struct ext4_dir_entry_2 *de,
2717 int blocksize, int csum_size,
2718 unsigned int parent_ino, int dotdot_real_len)
2719 {
2720 de->inode = cpu_to_le32(inode->i_ino);
2721 de->name_len = 1;
2722 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2723 blocksize);
2724 strcpy(de->name, ".");
2725 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2726
2727 de = ext4_next_entry(de, blocksize);
2728 de->inode = cpu_to_le32(parent_ino);
2729 de->name_len = 2;
2730 if (!dotdot_real_len)
2731 de->rec_len = ext4_rec_len_to_disk(blocksize -
2732 (csum_size + EXT4_DIR_REC_LEN(1)),
2733 blocksize);
2734 else
2735 de->rec_len = ext4_rec_len_to_disk(
2736 EXT4_DIR_REC_LEN(de->name_len), blocksize);
2737 strcpy(de->name, "..");
2738 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2739
2740 return ext4_next_entry(de, blocksize);
2741 }
2742
2743 static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2744 struct inode *inode)
2745 {
2746 struct buffer_head *dir_block = NULL;
2747 struct ext4_dir_entry_2 *de;
2748 ext4_lblk_t block = 0;
2749 unsigned int blocksize = dir->i_sb->s_blocksize;
2750 int csum_size = 0;
2751 int err;
2752
2753 if (ext4_has_metadata_csum(dir->i_sb))
2754 csum_size = sizeof(struct ext4_dir_entry_tail);
2755
2756 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
2757 err = ext4_try_create_inline_dir(handle, dir, inode);
2758 if (err < 0 && err != -ENOSPC)
2759 goto out;
2760 if (!err)
2761 goto out;
2762 }
2763
2764 inode->i_size = 0;
2765 dir_block = ext4_append(handle, inode, &block);
2766 if (IS_ERR(dir_block))
2767 return PTR_ERR(dir_block);
2768 de = (struct ext4_dir_entry_2 *)dir_block->b_data;
2769 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
2770 set_nlink(inode, 2);
2771 if (csum_size)
2772 ext4_initialize_dirent_tail(dir_block, blocksize);
2773
2774 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2775 err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
2776 if (err)
2777 goto out;
2778 set_buffer_verified(dir_block);
2779 out:
2780 brelse(dir_block);
2781 return err;
2782 }
2783
2784 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2785 {
2786 handle_t *handle;
2787 struct inode *inode;
2788 int err, err2 = 0, credits, retries = 0;
2789
2790 if (EXT4_DIR_LINK_MAX(dir))
2791 return -EMLINK;
2792
2793 err = dquot_initialize(dir);
2794 if (err)
2795 return err;
2796
2797 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2798 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2799 retry:
2800 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
2801 &dentry->d_name,
2802 0, NULL, EXT4_HT_DIR, credits);
2803 handle = ext4_journal_current_handle();
2804 err = PTR_ERR(inode);
2805 if (IS_ERR(inode))
2806 goto out_stop;
2807
2808 inode->i_op = &ext4_dir_inode_operations;
2809 inode->i_fop = &ext4_dir_operations;
2810 err = ext4_init_new_dir(handle, dir, inode);
2811 if (err)
2812 goto out_clear_inode;
2813 err = ext4_mark_inode_dirty(handle, inode);
2814 if (!err)
2815 err = ext4_add_entry(handle, dentry, inode);
2816 if (err) {
2817 out_clear_inode:
2818 clear_nlink(inode);
2819 ext4_orphan_add(handle, inode);
2820 unlock_new_inode(inode);
2821 err2 = ext4_mark_inode_dirty(handle, inode);
2822 if (unlikely(err2))
2823 err = err2;
2824 ext4_journal_stop(handle);
2825 iput(inode);
2826 goto out_retry;
2827 }
2828 ext4_inc_count(handle, dir);
2829 ext4_update_dx_flag(dir);
2830 err = ext4_mark_inode_dirty(handle, dir);
2831 if (err)
2832 goto out_clear_inode;
2833 d_instantiate_new(dentry, inode);
2834 if (IS_DIRSYNC(dir))
2835 ext4_handle_sync(handle);
2836
2837 out_stop:
2838 if (handle)
2839 ext4_journal_stop(handle);
2840 out_retry:
2841 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2842 goto retry;
2843 return err;
2844 }
2845
2846 /*
2847 * routine to check that the specified directory is empty (for rmdir)
2848 */
2849 bool ext4_empty_dir(struct inode *inode)
2850 {
2851 unsigned int offset;
2852 struct buffer_head *bh;
2853 struct ext4_dir_entry_2 *de;
2854 struct super_block *sb;
2855
2856 if (ext4_has_inline_data(inode)) {
2857 int has_inline_data = 1;
2858 int ret;
2859
2860 ret = empty_inline_dir(inode, &has_inline_data);
2861 if (has_inline_data)
2862 return ret;
2863 }
2864
2865 sb = inode->i_sb;
2866 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
2867 EXT4_ERROR_INODE(inode, "invalid size");
2868 return true;
2869 }
2870 /* The first directory block must not be a hole,
2871 * so treat it as DIRENT_HTREE
2872 */
2873 bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE);
2874 if (IS_ERR(bh))
2875 return true;
2876
2877 de = (struct ext4_dir_entry_2 *) bh->b_data;
2878 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
2879 0) ||
2880 le32_to_cpu(de->inode) != inode->i_ino || strcmp(".", de->name)) {
2881 ext4_warning_inode(inode, "directory missing '.'");
2882 brelse(bh);
2883 return true;
2884 }
2885 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2886 de = ext4_next_entry(de, sb->s_blocksize);
2887 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
2888 offset) ||
2889 le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) {
2890 ext4_warning_inode(inode, "directory missing '..'");
2891 brelse(bh);
2892 return true;
2893 }
2894 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2895 while (offset < inode->i_size) {
2896 if (!(offset & (sb->s_blocksize - 1))) {
2897 unsigned int lblock;
2898 brelse(bh);
2899 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
2900 bh = ext4_read_dirblock(inode, lblock, EITHER);
2901 if (bh == NULL) {
2902 offset += sb->s_blocksize;
2903 continue;
2904 }
2905 if (IS_ERR(bh))
2906 return true;
2907 }
2908 de = (struct ext4_dir_entry_2 *) (bh->b_data +
2909 (offset & (sb->s_blocksize - 1)));
2910 if (ext4_check_dir_entry(inode, NULL, de, bh,
2911 bh->b_data, bh->b_size, offset)) {
2912 offset = (offset | (sb->s_blocksize - 1)) + 1;
2913 continue;
2914 }
2915 if (le32_to_cpu(de->inode)) {
2916 brelse(bh);
2917 return false;
2918 }
2919 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2920 }
2921 brelse(bh);
2922 return true;
2923 }
2924
2925 /*
2926 * ext4_orphan_add() links an unlinked or truncated inode into a list of
2927 * such inodes, starting at the superblock, in case we crash before the
2928 * file is closed/deleted, or in case the inode truncate spans multiple
2929 * transactions and the last transaction is not recovered after a crash.
2930 *
2931 * At filesystem recovery time, we walk this list deleting unlinked
2932 * inodes and truncating linked inodes in ext4_orphan_cleanup().
2933 *
2934 * Orphan list manipulation functions must be called under i_mutex unless
2935 * we are just creating the inode or deleting it.
2936 */
2937 int ext4_orphan_add(handle_t *handle, struct inode *inode)
2938 {
2939 struct super_block *sb = inode->i_sb;
2940 struct ext4_sb_info *sbi = EXT4_SB(sb);
2941 struct ext4_iloc iloc;
2942 int err = 0, rc;
2943 bool dirty = false;
2944
2945 if (!sbi->s_journal || is_bad_inode(inode))
2946 return 0;
2947
2948 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
2949 !inode_is_locked(inode));
2950 /*
2951 * Exit early if inode already is on orphan list. This is a big speedup
2952 * since we don't have to contend on the global s_orphan_lock.
2953 */
2954 if (!list_empty(&EXT4_I(inode)->i_orphan))
2955 return 0;
2956
2957 /*
2958 * Orphan handling is only valid for files with data blocks
2959 * being truncated, or files being unlinked. Note that we either
2960 * hold i_mutex, or the inode can not be referenced from outside,
2961 * so i_nlink should not be bumped due to race
2962 */
2963 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2964 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
2965
2966 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2967 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
2968 if (err)
2969 goto out;
2970
2971 err = ext4_reserve_inode_write(handle, inode, &iloc);
2972 if (err)
2973 goto out;
2974
2975 mutex_lock(&sbi->s_orphan_lock);
2976 /*
2977 * Due to previous errors inode may be already a part of on-disk
2978 * orphan list. If so skip on-disk list modification.
2979 */
2980 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
2981 (le32_to_cpu(sbi->s_es->s_inodes_count))) {
2982 /* Insert this inode at the head of the on-disk orphan list */
2983 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
2984 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2985 dirty = true;
2986 }
2987 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
2988 mutex_unlock(&sbi->s_orphan_lock);
2989
2990 if (dirty) {
2991 err = ext4_handle_dirty_super(handle, sb);
2992 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
2993 if (!err)
2994 err = rc;
2995 if (err) {
2996 /*
2997 * We have to remove inode from in-memory list if
2998 * addition to on disk orphan list failed. Stray orphan
2999 * list entries can cause panics at unmount time.
3000 */
3001 mutex_lock(&sbi->s_orphan_lock);
3002 list_del_init(&EXT4_I(inode)->i_orphan);
3003 mutex_unlock(&sbi->s_orphan_lock);
3004 }
3005 } else
3006 brelse(iloc.bh);
3007
3008 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
3009 jbd_debug(4, "orphan inode %lu will point to %d\n",
3010 inode->i_ino, NEXT_ORPHAN(inode));
3011 out:
3012 ext4_std_error(sb, err);
3013 return err;
3014 }
3015
3016 /*
3017 * ext4_orphan_del() removes an unlinked or truncated inode from the list
3018 * of such inodes stored on disk, because it is finally being cleaned up.
3019 */
3020 int ext4_orphan_del(handle_t *handle, struct inode *inode)
3021 {
3022 struct list_head *prev;
3023 struct ext4_inode_info *ei = EXT4_I(inode);
3024 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3025 __u32 ino_next;
3026 struct ext4_iloc iloc;
3027 int err = 0;
3028
3029 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
3030 return 0;
3031
3032 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
3033 !inode_is_locked(inode));
3034 /* Do this quick check before taking global s_orphan_lock. */
3035 if (list_empty(&ei->i_orphan))
3036 return 0;
3037
3038 if (handle) {
3039 /* Grab inode buffer early before taking global s_orphan_lock */
3040 err = ext4_reserve_inode_write(handle, inode, &iloc);
3041 }
3042
3043 mutex_lock(&sbi->s_orphan_lock);
3044 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
3045
3046 prev = ei->i_orphan.prev;
3047 list_del_init(&ei->i_orphan);
3048
3049 /* If we're on an error path, we may not have a valid
3050 * transaction handle with which to update the orphan list on
3051 * disk, but we still need to remove the inode from the linked
3052 * list in memory. */
3053 if (!handle || err) {
3054 mutex_unlock(&sbi->s_orphan_lock);
3055 goto out_err;
3056 }
3057
3058 ino_next = NEXT_ORPHAN(inode);
3059 if (prev == &sbi->s_orphan) {
3060 jbd_debug(4, "superblock will point to %u\n", ino_next);
3061 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
3062 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
3063 if (err) {
3064 mutex_unlock(&sbi->s_orphan_lock);
3065 goto out_brelse;
3066 }
3067 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
3068 mutex_unlock(&sbi->s_orphan_lock);
3069 err = ext4_handle_dirty_super(handle, inode->i_sb);
3070 } else {
3071 struct ext4_iloc iloc2;
3072 struct inode *i_prev =
3073 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
3074
3075 jbd_debug(4, "orphan inode %lu will point to %u\n",
3076 i_prev->i_ino, ino_next);
3077 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
3078 if (err) {
3079 mutex_unlock(&sbi->s_orphan_lock);
3080 goto out_brelse;
3081 }
3082 NEXT_ORPHAN(i_prev) = ino_next;
3083 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
3084 mutex_unlock(&sbi->s_orphan_lock);
3085 }
3086 if (err)
3087 goto out_brelse;
3088 NEXT_ORPHAN(inode) = 0;
3089 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
3090 out_err:
3091 ext4_std_error(inode->i_sb, err);
3092 return err;
3093
3094 out_brelse:
3095 brelse(iloc.bh);
3096 goto out_err;
3097 }
3098
3099 static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
3100 {
3101 int retval;
3102 struct inode *inode;
3103 struct buffer_head *bh;
3104 struct ext4_dir_entry_2 *de;
3105 handle_t *handle = NULL;
3106
3107 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3108 return -EIO;
3109
3110 /* Initialize quotas before so that eventual writes go in
3111 * separate transaction */
3112 retval = dquot_initialize(dir);
3113 if (retval)
3114 return retval;
3115 retval = dquot_initialize(d_inode(dentry));
3116 if (retval)
3117 return retval;
3118
3119 retval = -ENOENT;
3120 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
3121 if (IS_ERR(bh))
3122 return PTR_ERR(bh);
3123 if (!bh)
3124 goto end_rmdir;
3125
3126 inode = d_inode(dentry);
3127
3128 retval = -EFSCORRUPTED;
3129 if (le32_to_cpu(de->inode) != inode->i_ino)
3130 goto end_rmdir;
3131
3132 retval = -ENOTEMPTY;
3133 if (!ext4_empty_dir(inode))
3134 goto end_rmdir;
3135
3136 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3137 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3138 if (IS_ERR(handle)) {
3139 retval = PTR_ERR(handle);
3140 handle = NULL;
3141 goto end_rmdir;
3142 }
3143
3144 if (IS_DIRSYNC(dir))
3145 ext4_handle_sync(handle);
3146
3147 retval = ext4_delete_entry(handle, dir, de, bh);
3148 if (retval)
3149 goto end_rmdir;
3150 if (!EXT4_DIR_LINK_EMPTY(inode))
3151 ext4_warning_inode(inode,
3152 "empty directory '%.*s' has too many links (%u)",
3153 dentry->d_name.len, dentry->d_name.name,
3154 inode->i_nlink);
3155 inode_inc_iversion(inode);
3156 clear_nlink(inode);
3157 /* There's no need to set i_disksize: the fact that i_nlink is
3158 * zero will ensure that the right thing happens during any
3159 * recovery. */
3160 inode->i_size = 0;
3161 ext4_orphan_add(handle, inode);
3162 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode);
3163 retval = ext4_mark_inode_dirty(handle, inode);
3164 if (retval)
3165 goto end_rmdir;
3166 ext4_dec_count(handle, dir);
3167 ext4_update_dx_flag(dir);
3168 retval = ext4_mark_inode_dirty(handle, dir);
3169
3170 #ifdef CONFIG_UNICODE
3171 /* VFS negative dentries are incompatible with Encoding and
3172 * Case-insensitiveness. Eventually we'll want avoid
3173 * invalidating the dentries here, alongside with returning the
3174 * negative dentries at ext4_lookup(), when it is better
3175 * supported by the VFS for the CI case.
3176 */
3177 if (IS_CASEFOLDED(dir))
3178 d_invalidate(dentry);
3179 #endif
3180
3181 end_rmdir:
3182 brelse(bh);
3183 if (handle)
3184 ext4_journal_stop(handle);
3185 return retval;
3186 }
3187
3188 static int ext4_unlink(struct inode *dir, struct dentry *dentry)
3189 {
3190 int retval;
3191 struct inode *inode;
3192 struct buffer_head *bh;
3193 struct ext4_dir_entry_2 *de;
3194 handle_t *handle = NULL;
3195
3196 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3197 return -EIO;
3198
3199 trace_ext4_unlink_enter(dir, dentry);
3200 /* Initialize quotas before so that eventual writes go
3201 * in separate transaction */
3202 retval = dquot_initialize(dir);
3203 if (retval)
3204 goto out_trace;
3205 retval = dquot_initialize(d_inode(dentry));
3206 if (retval)
3207 goto out_trace;
3208
3209 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
3210 if (IS_ERR(bh)) {
3211 retval = PTR_ERR(bh);
3212 goto out_trace;
3213 }
3214 if (!bh) {
3215 retval = -ENOENT;
3216 goto out_trace;
3217 }
3218
3219 inode = d_inode(dentry);
3220
3221 if (le32_to_cpu(de->inode) != inode->i_ino) {
3222 retval = -EFSCORRUPTED;
3223 goto out_bh;
3224 }
3225
3226 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3227 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3228 if (IS_ERR(handle)) {
3229 retval = PTR_ERR(handle);
3230 goto out_bh;
3231 }
3232
3233 if (IS_DIRSYNC(dir))
3234 ext4_handle_sync(handle);
3235
3236 retval = ext4_delete_entry(handle, dir, de, bh);
3237 if (retval)
3238 goto out_handle;
3239 dir->i_ctime = dir->i_mtime = current_time(dir);
3240 ext4_update_dx_flag(dir);
3241 retval = ext4_mark_inode_dirty(handle, dir);
3242 if (retval)
3243 goto out_handle;
3244 if (inode->i_nlink == 0)
3245 ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
3246 dentry->d_name.len, dentry->d_name.name);
3247 else
3248 drop_nlink(inode);
3249 if (!inode->i_nlink)
3250 ext4_orphan_add(handle, inode);
3251 inode->i_ctime = current_time(inode);
3252 retval = ext4_mark_inode_dirty(handle, inode);
3253
3254 #ifdef CONFIG_UNICODE
3255 /* VFS negative dentries are incompatible with Encoding and
3256 * Case-insensitiveness. Eventually we'll want avoid
3257 * invalidating the dentries here, alongside with returning the
3258 * negative dentries at ext4_lookup(), when it is better
3259 * supported by the VFS for the CI case.
3260 */
3261 if (IS_CASEFOLDED(dir))
3262 d_invalidate(dentry);
3263 #endif
3264
3265 out_handle:
3266 ext4_journal_stop(handle);
3267 out_bh:
3268 brelse(bh);
3269 out_trace:
3270 trace_ext4_unlink_exit(dentry, retval);
3271 return retval;
3272 }
3273
3274 static int ext4_symlink(struct inode *dir,
3275 struct dentry *dentry, const char *symname)
3276 {
3277 handle_t *handle;
3278 struct inode *inode;
3279 int err, len = strlen(symname);
3280 int credits;
3281 struct fscrypt_str disk_link;
3282
3283 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3284 return -EIO;
3285
3286 err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,
3287 &disk_link);
3288 if (err)
3289 return err;
3290
3291 err = dquot_initialize(dir);
3292 if (err)
3293 return err;
3294
3295 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3296 /*
3297 * For non-fast symlinks, we just allocate inode and put it on
3298 * orphan list in the first transaction => we need bitmap,
3299 * group descriptor, sb, inode block, quota blocks, and
3300 * possibly selinux xattr blocks.
3301 */
3302 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
3303 EXT4_XATTR_TRANS_BLOCKS;
3304 } else {
3305 /*
3306 * Fast symlink. We have to add entry to directory
3307 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
3308 * allocate new inode (bitmap, group descriptor, inode block,
3309 * quota blocks, sb is already counted in previous macros).
3310 */
3311 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3312 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
3313 }
3314
3315 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
3316 &dentry->d_name, 0, NULL,
3317 EXT4_HT_DIR, credits);
3318 handle = ext4_journal_current_handle();
3319 if (IS_ERR(inode)) {
3320 if (handle)
3321 ext4_journal_stop(handle);
3322 return PTR_ERR(inode);
3323 }
3324
3325 if (IS_ENCRYPTED(inode)) {
3326 err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
3327 if (err)
3328 goto err_drop_inode;
3329 inode->i_op = &ext4_encrypted_symlink_inode_operations;
3330 }
3331
3332 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3333 if (!IS_ENCRYPTED(inode))
3334 inode->i_op = &ext4_symlink_inode_operations;
3335 inode_nohighmem(inode);
3336 ext4_set_aops(inode);
3337 /*
3338 * We cannot call page_symlink() with transaction started
3339 * because it calls into ext4_write_begin() which can wait
3340 * for transaction commit if we are running out of space
3341 * and thus we deadlock. So we have to stop transaction now
3342 * and restart it when symlink contents is written.
3343 *
3344 * To keep fs consistent in case of crash, we have to put inode
3345 * to orphan list in the mean time.
3346 */
3347 drop_nlink(inode);
3348 err = ext4_orphan_add(handle, inode);
3349 ext4_journal_stop(handle);
3350 handle = NULL;
3351 if (err)
3352 goto err_drop_inode;
3353 err = __page_symlink(inode, disk_link.name, disk_link.len, 1);
3354 if (err)
3355 goto err_drop_inode;
3356 /*
3357 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
3358 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
3359 */
3360 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3361 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3362 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
3363 if (IS_ERR(handle)) {
3364 err = PTR_ERR(handle);
3365 handle = NULL;
3366 goto err_drop_inode;
3367 }
3368 set_nlink(inode, 1);
3369 err = ext4_orphan_del(handle, inode);
3370 if (err)
3371 goto err_drop_inode;
3372 } else {
3373 /* clear the extent format for fast symlink */
3374 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
3375 if (!IS_ENCRYPTED(inode)) {
3376 inode->i_op = &ext4_fast_symlink_inode_operations;
3377 inode->i_link = (char *)&EXT4_I(inode)->i_data;
3378 }
3379 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name,
3380 disk_link.len);
3381 inode->i_size = disk_link.len - 1;
3382 }
3383 EXT4_I(inode)->i_disksize = inode->i_size;
3384 err = ext4_add_nondir(handle, dentry, &inode);
3385 if (handle)
3386 ext4_journal_stop(handle);
3387 if (inode)
3388 iput(inode);
3389 goto out_free_encrypted_link;
3390
3391 err_drop_inode:
3392 if (handle)
3393 ext4_journal_stop(handle);
3394 clear_nlink(inode);
3395 unlock_new_inode(inode);
3396 iput(inode);
3397 out_free_encrypted_link:
3398 if (disk_link.name != (unsigned char *)symname)
3399 kfree(disk_link.name);
3400 return err;
3401 }
3402
3403 static int ext4_link(struct dentry *old_dentry,
3404 struct inode *dir, struct dentry *dentry)
3405 {
3406 handle_t *handle;
3407 struct inode *inode = d_inode(old_dentry);
3408 int err, retries = 0;
3409
3410 if (inode->i_nlink >= EXT4_LINK_MAX)
3411 return -EMLINK;
3412
3413 err = fscrypt_prepare_link(old_dentry, dir, dentry);
3414 if (err)
3415 return err;
3416
3417 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) &&
3418 (!projid_eq(EXT4_I(dir)->i_projid,
3419 EXT4_I(old_dentry->d_inode)->i_projid)))
3420 return -EXDEV;
3421
3422 err = dquot_initialize(dir);
3423 if (err)
3424 return err;
3425
3426 retry:
3427 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3428 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3429 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
3430 if (IS_ERR(handle))
3431 return PTR_ERR(handle);
3432
3433 if (IS_DIRSYNC(dir))
3434 ext4_handle_sync(handle);
3435
3436 inode->i_ctime = current_time(inode);
3437 ext4_inc_count(handle, inode);
3438 ihold(inode);
3439
3440 err = ext4_add_entry(handle, dentry, inode);
3441 if (!err) {
3442 err = ext4_mark_inode_dirty(handle, inode);
3443 /* this can happen only for tmpfile being
3444 * linked the first time
3445 */
3446 if (inode->i_nlink == 1)
3447 ext4_orphan_del(handle, inode);
3448 d_instantiate(dentry, inode);
3449 } else {
3450 drop_nlink(inode);
3451 iput(inode);
3452 }
3453 ext4_journal_stop(handle);
3454 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
3455 goto retry;
3456 return err;
3457 }
3458
3459
3460 /*
3461 * Try to find buffer head where contains the parent block.
3462 * It should be the inode block if it is inlined or the 1st block
3463 * if it is a normal dir.
3464 */
3465 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
3466 struct inode *inode,
3467 int *retval,
3468 struct ext4_dir_entry_2 **parent_de,
3469 int *inlined)
3470 {
3471 struct buffer_head *bh;
3472
3473 if (!ext4_has_inline_data(inode)) {
3474 /* The first directory block must not be a hole, so
3475 * treat it as DIRENT_HTREE
3476 */
3477 bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE);
3478 if (IS_ERR(bh)) {
3479 *retval = PTR_ERR(bh);
3480 return NULL;
3481 }
3482 *parent_de = ext4_next_entry(
3483 (struct ext4_dir_entry_2 *)bh->b_data,
3484 inode->i_sb->s_blocksize);
3485 return bh;
3486 }
3487
3488 *inlined = 1;
3489 return ext4_get_first_inline_block(inode, parent_de, retval);
3490 }
3491
3492 struct ext4_renament {
3493 struct inode *dir;
3494 struct dentry *dentry;
3495 struct inode *inode;
3496 bool is_dir;
3497 int dir_nlink_delta;
3498
3499 /* entry for "dentry" */
3500 struct buffer_head *bh;
3501 struct ext4_dir_entry_2 *de;
3502 int inlined;
3503
3504 /* entry for ".." in inode if it's a directory */
3505 struct buffer_head *dir_bh;
3506 struct ext4_dir_entry_2 *parent_de;
3507 int dir_inlined;
3508 };
3509
3510 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
3511 {
3512 int retval;
3513
3514 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
3515 &retval, &ent->parent_de,
3516 &ent->dir_inlined);
3517 if (!ent->dir_bh)
3518 return retval;
3519 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
3520 return -EFSCORRUPTED;
3521 BUFFER_TRACE(ent->dir_bh, "get_write_access");
3522 return ext4_journal_get_write_access(handle, ent->dir_bh);
3523 }
3524
3525 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
3526 unsigned dir_ino)
3527 {
3528 int retval;
3529
3530 ent->parent_de->inode = cpu_to_le32(dir_ino);
3531 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
3532 if (!ent->dir_inlined) {
3533 if (is_dx(ent->inode)) {
3534 retval = ext4_handle_dirty_dx_node(handle,
3535 ent->inode,
3536 ent->dir_bh);
3537 } else {
3538 retval = ext4_handle_dirty_dirblock(handle, ent->inode,
3539 ent->dir_bh);
3540 }
3541 } else {
3542 retval = ext4_mark_inode_dirty(handle, ent->inode);
3543 }
3544 if (retval) {
3545 ext4_std_error(ent->dir->i_sb, retval);
3546 return retval;
3547 }
3548 return 0;
3549 }
3550
3551 static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
3552 unsigned ino, unsigned file_type)
3553 {
3554 int retval, retval2;
3555
3556 BUFFER_TRACE(ent->bh, "get write access");
3557 retval = ext4_journal_get_write_access(handle, ent->bh);
3558 if (retval)
3559 return retval;
3560 ent->de->inode = cpu_to_le32(ino);
3561 if (ext4_has_feature_filetype(ent->dir->i_sb))
3562 ent->de->file_type = file_type;
3563 inode_inc_iversion(ent->dir);
3564 ent->dir->i_ctime = ent->dir->i_mtime =
3565 current_time(ent->dir);
3566 retval = ext4_mark_inode_dirty(handle, ent->dir);
3567 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
3568 if (!ent->inlined) {
3569 retval2 = ext4_handle_dirty_dirblock(handle, ent->dir, ent->bh);
3570 if (unlikely(retval2)) {
3571 ext4_std_error(ent->dir->i_sb, retval2);
3572 return retval2;
3573 }
3574 }
3575 brelse(ent->bh);
3576 ent->bh = NULL;
3577
3578 return retval;
3579 }
3580
3581 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
3582 const struct qstr *d_name)
3583 {
3584 int retval = -ENOENT;
3585 struct buffer_head *bh;
3586 struct ext4_dir_entry_2 *de;
3587
3588 bh = ext4_find_entry(dir, d_name, &de, NULL);
3589 if (IS_ERR(bh))
3590 return PTR_ERR(bh);
3591 if (bh) {
3592 retval = ext4_delete_entry(handle, dir, de, bh);
3593 brelse(bh);
3594 }
3595 return retval;
3596 }
3597
3598 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent,
3599 int force_reread)
3600 {
3601 int retval;
3602 /*
3603 * ent->de could have moved from under us during htree split, so make
3604 * sure that we are deleting the right entry. We might also be pointing
3605 * to a stale entry in the unused part of ent->bh so just checking inum
3606 * and the name isn't enough.
3607 */
3608 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
3609 ent->de->name_len != ent->dentry->d_name.len ||
3610 strncmp(ent->de->name, ent->dentry->d_name.name,
3611 ent->de->name_len) ||
3612 force_reread) {
3613 retval = ext4_find_delete_entry(handle, ent->dir,
3614 &ent->dentry->d_name);
3615 } else {
3616 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
3617 if (retval == -ENOENT) {
3618 retval = ext4_find_delete_entry(handle, ent->dir,
3619 &ent->dentry->d_name);
3620 }
3621 }
3622
3623 if (retval) {
3624 ext4_warning_inode(ent->dir,
3625 "Deleting old file: nlink %d, error=%d",
3626 ent->dir->i_nlink, retval);
3627 }
3628 }
3629
3630 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
3631 {
3632 if (ent->dir_nlink_delta) {
3633 if (ent->dir_nlink_delta == -1)
3634 ext4_dec_count(handle, ent->dir);
3635 else
3636 ext4_inc_count(handle, ent->dir);
3637 ext4_mark_inode_dirty(handle, ent->dir);
3638 }
3639 }
3640
3641 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
3642 int credits, handle_t **h)
3643 {
3644 struct inode *wh;
3645 handle_t *handle;
3646 int retries = 0;
3647
3648 /*
3649 * for inode block, sb block, group summaries,
3650 * and inode bitmap
3651 */
3652 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
3653 EXT4_XATTR_TRANS_BLOCKS + 4);
3654 retry:
3655 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE,
3656 &ent->dentry->d_name, 0, NULL,
3657 EXT4_HT_DIR, credits);
3658
3659 handle = ext4_journal_current_handle();
3660 if (IS_ERR(wh)) {
3661 if (handle)
3662 ext4_journal_stop(handle);
3663 if (PTR_ERR(wh) == -ENOSPC &&
3664 ext4_should_retry_alloc(ent->dir->i_sb, &retries))
3665 goto retry;
3666 } else {
3667 *h = handle;
3668 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);
3669 wh->i_op = &ext4_special_inode_operations;
3670 }
3671 return wh;
3672 }
3673
3674 /*
3675 * Anybody can rename anything with this: the permission checks are left to the
3676 * higher-level routines.
3677 *
3678 * n.b. old_{dentry,inode) refers to the source dentry/inode
3679 * while new_{dentry,inode) refers to the destination dentry/inode
3680 * This comes from rename(const char *oldpath, const char *newpath)
3681 */
3682 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
3683 struct inode *new_dir, struct dentry *new_dentry,
3684 unsigned int flags)
3685 {
3686 handle_t *handle = NULL;
3687 struct ext4_renament old = {
3688 .dir = old_dir,
3689 .dentry = old_dentry,
3690 .inode = d_inode(old_dentry),
3691 };
3692 struct ext4_renament new = {
3693 .dir = new_dir,
3694 .dentry = new_dentry,
3695 .inode = d_inode(new_dentry),
3696 };
3697 int force_reread;
3698 int retval;
3699 struct inode *whiteout = NULL;
3700 int credits;
3701 u8 old_file_type;
3702
3703 if (new.inode && new.inode->i_nlink == 0) {
3704 EXT4_ERROR_INODE(new.inode,
3705 "target of rename is already freed");
3706 return -EFSCORRUPTED;
3707 }
3708
3709 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) &&
3710 (!projid_eq(EXT4_I(new_dir)->i_projid,
3711 EXT4_I(old_dentry->d_inode)->i_projid)))
3712 return -EXDEV;
3713
3714 retval = dquot_initialize(old.dir);
3715 if (retval)
3716 return retval;
3717 retval = dquot_initialize(new.dir);
3718 if (retval)
3719 return retval;
3720
3721 /* Initialize quotas before so that eventual writes go
3722 * in separate transaction */
3723 if (new.inode) {
3724 retval = dquot_initialize(new.inode);
3725 if (retval)
3726 return retval;
3727 }
3728
3729 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
3730 if (IS_ERR(old.bh))
3731 return PTR_ERR(old.bh);
3732 /*
3733 * Check for inode number is _not_ due to possible IO errors.
3734 * We might rmdir the source, keep it as pwd of some process
3735 * and merrily kill the link to whatever was created under the
3736 * same name. Goodbye sticky bit ;-<
3737 */
3738 retval = -ENOENT;
3739 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3740 goto end_rename;
3741
3742 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3743 &new.de, &new.inlined);
3744 if (IS_ERR(new.bh)) {
3745 retval = PTR_ERR(new.bh);
3746 new.bh = NULL;
3747 goto end_rename;
3748 }
3749 if (new.bh) {
3750 if (!new.inode) {
3751 brelse(new.bh);
3752 new.bh = NULL;
3753 }
3754 }
3755 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
3756 ext4_alloc_da_blocks(old.inode);
3757
3758 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3759 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
3760 if (!(flags & RENAME_WHITEOUT)) {
3761 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);
3762 if (IS_ERR(handle)) {
3763 retval = PTR_ERR(handle);
3764 handle = NULL;
3765 goto end_rename;
3766 }
3767 } else {
3768 whiteout = ext4_whiteout_for_rename(&old, credits, &handle);
3769 if (IS_ERR(whiteout)) {
3770 retval = PTR_ERR(whiteout);
3771 whiteout = NULL;
3772 goto end_rename;
3773 }
3774 }
3775
3776 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3777 ext4_handle_sync(handle);
3778
3779 if (S_ISDIR(old.inode->i_mode)) {
3780 if (new.inode) {
3781 retval = -ENOTEMPTY;
3782 if (!ext4_empty_dir(new.inode))
3783 goto end_rename;
3784 } else {
3785 retval = -EMLINK;
3786 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
3787 goto end_rename;
3788 }
3789 retval = ext4_rename_dir_prepare(handle, &old);
3790 if (retval)
3791 goto end_rename;
3792 }
3793 /*
3794 * If we're renaming a file within an inline_data dir and adding or
3795 * setting the new dirent causes a conversion from inline_data to
3796 * extents/blockmap, we need to force the dirent delete code to
3797 * re-read the directory, or else we end up trying to delete a dirent
3798 * from what is now the extent tree root (or a block map).
3799 */
3800 force_reread = (new.dir->i_ino == old.dir->i_ino &&
3801 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA));
3802
3803 old_file_type = old.de->file_type;
3804 if (whiteout) {
3805 /*
3806 * Do this before adding a new entry, so the old entry is sure
3807 * to be still pointing to the valid old entry.
3808 */
3809 retval = ext4_setent(handle, &old, whiteout->i_ino,
3810 EXT4_FT_CHRDEV);
3811 if (retval)
3812 goto end_rename;
3813 retval = ext4_mark_inode_dirty(handle, whiteout);
3814 if (unlikely(retval))
3815 goto end_rename;
3816 }
3817 if (!new.bh) {
3818 retval = ext4_add_entry(handle, new.dentry, old.inode);
3819 if (retval)
3820 goto end_rename;
3821 } else {
3822 retval = ext4_setent(handle, &new,
3823 old.inode->i_ino, old_file_type);
3824 if (retval)
3825 goto end_rename;
3826 }
3827 if (force_reread)
3828 force_reread = !ext4_test_inode_flag(new.dir,
3829 EXT4_INODE_INLINE_DATA);
3830
3831 /*
3832 * Like most other Unix systems, set the ctime for inodes on a
3833 * rename.
3834 */
3835 old.inode->i_ctime = current_time(old.inode);
3836 retval = ext4_mark_inode_dirty(handle, old.inode);
3837 if (unlikely(retval))
3838 goto end_rename;
3839
3840 if (!whiteout) {
3841 /*
3842 * ok, that's it
3843 */
3844 ext4_rename_delete(handle, &old, force_reread);
3845 }
3846
3847 if (new.inode) {
3848 ext4_dec_count(handle, new.inode);
3849 new.inode->i_ctime = current_time(new.inode);
3850 }
3851 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir);
3852 ext4_update_dx_flag(old.dir);
3853 if (old.dir_bh) {
3854 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3855 if (retval)
3856 goto end_rename;
3857
3858 ext4_dec_count(handle, old.dir);
3859 if (new.inode) {
3860 /* checked ext4_empty_dir above, can't have another
3861 * parent, ext4_dec_count() won't work for many-linked
3862 * dirs */
3863 clear_nlink(new.inode);
3864 } else {
3865 ext4_inc_count(handle, new.dir);
3866 ext4_update_dx_flag(new.dir);
3867 retval = ext4_mark_inode_dirty(handle, new.dir);
3868 if (unlikely(retval))
3869 goto end_rename;
3870 }
3871 }
3872 retval = ext4_mark_inode_dirty(handle, old.dir);
3873 if (unlikely(retval))
3874 goto end_rename;
3875 if (new.inode) {
3876 retval = ext4_mark_inode_dirty(handle, new.inode);
3877 if (unlikely(retval))
3878 goto end_rename;
3879 if (!new.inode->i_nlink)
3880 ext4_orphan_add(handle, new.inode);
3881 }
3882 retval = 0;
3883
3884 end_rename:
3885 brelse(old.dir_bh);
3886 brelse(old.bh);
3887 brelse(new.bh);
3888 if (whiteout) {
3889 if (retval)
3890 drop_nlink(whiteout);
3891 unlock_new_inode(whiteout);
3892 iput(whiteout);
3893 }
3894 if (handle)
3895 ext4_journal_stop(handle);
3896 return retval;
3897 }
3898
3899 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
3900 struct inode *new_dir, struct dentry *new_dentry)
3901 {
3902 handle_t *handle = NULL;
3903 struct ext4_renament old = {
3904 .dir = old_dir,
3905 .dentry = old_dentry,
3906 .inode = d_inode(old_dentry),
3907 };
3908 struct ext4_renament new = {
3909 .dir = new_dir,
3910 .dentry = new_dentry,
3911 .inode = d_inode(new_dentry),
3912 };
3913 u8 new_file_type;
3914 int retval;
3915 struct timespec64 ctime;
3916
3917 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&
3918 !projid_eq(EXT4_I(new_dir)->i_projid,
3919 EXT4_I(old_dentry->d_inode)->i_projid)) ||
3920 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) &&
3921 !projid_eq(EXT4_I(old_dir)->i_projid,
3922 EXT4_I(new_dentry->d_inode)->i_projid)))
3923 return -EXDEV;
3924
3925 retval = dquot_initialize(old.dir);
3926 if (retval)
3927 return retval;
3928 retval = dquot_initialize(new.dir);
3929 if (retval)
3930 return retval;
3931
3932 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
3933 &old.de, &old.inlined);
3934 if (IS_ERR(old.bh))
3935 return PTR_ERR(old.bh);
3936 /*
3937 * Check for inode number is _not_ due to possible IO errors.
3938 * We might rmdir the source, keep it as pwd of some process
3939 * and merrily kill the link to whatever was created under the
3940 * same name. Goodbye sticky bit ;-<
3941 */
3942 retval = -ENOENT;
3943 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3944 goto end_rename;
3945
3946 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3947 &new.de, &new.inlined);
3948 if (IS_ERR(new.bh)) {
3949 retval = PTR_ERR(new.bh);
3950 new.bh = NULL;
3951 goto end_rename;
3952 }
3953
3954 /* RENAME_EXCHANGE case: old *and* new must both exist */
3955 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
3956 goto end_rename;
3957
3958 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
3959 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3960 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
3961 if (IS_ERR(handle)) {
3962 retval = PTR_ERR(handle);
3963 handle = NULL;
3964 goto end_rename;
3965 }
3966
3967 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3968 ext4_handle_sync(handle);
3969
3970 if (S_ISDIR(old.inode->i_mode)) {
3971 old.is_dir = true;
3972 retval = ext4_rename_dir_prepare(handle, &old);
3973 if (retval)
3974 goto end_rename;
3975 }
3976 if (S_ISDIR(new.inode->i_mode)) {
3977 new.is_dir = true;
3978 retval = ext4_rename_dir_prepare(handle, &new);
3979 if (retval)
3980 goto end_rename;
3981 }
3982
3983 /*
3984 * Other than the special case of overwriting a directory, parents'
3985 * nlink only needs to be modified if this is a cross directory rename.
3986 */
3987 if (old.dir != new.dir && old.is_dir != new.is_dir) {
3988 old.dir_nlink_delta = old.is_dir ? -1 : 1;
3989 new.dir_nlink_delta = -old.dir_nlink_delta;
3990 retval = -EMLINK;
3991 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
3992 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
3993 goto end_rename;
3994 }
3995
3996 new_file_type = new.de->file_type;
3997 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
3998 if (retval)
3999 goto end_rename;
4000
4001 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
4002 if (retval)
4003 goto end_rename;
4004
4005 /*
4006 * Like most other Unix systems, set the ctime for inodes on a
4007 * rename.
4008 */
4009 ctime = current_time(old.inode);
4010 old.inode->i_ctime = ctime;
4011 new.inode->i_ctime = ctime;
4012 retval = ext4_mark_inode_dirty(handle, old.inode);
4013 if (unlikely(retval))
4014 goto end_rename;
4015 retval = ext4_mark_inode_dirty(handle, new.inode);
4016 if (unlikely(retval))
4017 goto end_rename;
4018
4019 if (old.dir_bh) {
4020 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
4021 if (retval)
4022 goto end_rename;
4023 }
4024 if (new.dir_bh) {
4025 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
4026 if (retval)
4027 goto end_rename;
4028 }
4029 ext4_update_dir_count(handle, &old);
4030 ext4_update_dir_count(handle, &new);
4031 retval = 0;
4032
4033 end_rename:
4034 brelse(old.dir_bh);
4035 brelse(new.dir_bh);
4036 brelse(old.bh);
4037 brelse(new.bh);
4038 if (handle)
4039 ext4_journal_stop(handle);
4040 return retval;
4041 }
4042
4043 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
4044 struct inode *new_dir, struct dentry *new_dentry,
4045 unsigned int flags)
4046 {
4047 int err;
4048
4049 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb))))
4050 return -EIO;
4051
4052 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
4053 return -EINVAL;
4054
4055 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
4056 flags);
4057 if (err)
4058 return err;
4059
4060 if (flags & RENAME_EXCHANGE) {
4061 return ext4_cross_rename(old_dir, old_dentry,
4062 new_dir, new_dentry);
4063 }
4064
4065 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
4066 }
4067
4068 /*
4069 * directories can handle most operations...
4070 */
4071 const struct inode_operations ext4_dir_inode_operations = {
4072 .create = ext4_create,
4073 .lookup = ext4_lookup,
4074 .link = ext4_link,
4075 .unlink = ext4_unlink,
4076 .symlink = ext4_symlink,
4077 .mkdir = ext4_mkdir,
4078 .rmdir = ext4_rmdir,
4079 .mknod = ext4_mknod,
4080 .tmpfile = ext4_tmpfile,
4081 .rename = ext4_rename2,
4082 .setattr = ext4_setattr,
4083 .getattr = ext4_getattr,
4084 .listxattr = ext4_listxattr,
4085 .get_acl = ext4_get_acl,
4086 .set_acl = ext4_set_acl,
4087 .fiemap = ext4_fiemap,
4088 };
4089
4090 const struct inode_operations ext4_special_inode_operations = {
4091 .setattr = ext4_setattr,
4092 .getattr = ext4_getattr,
4093 .listxattr = ext4_listxattr,
4094 .get_acl = ext4_get_acl,
4095 .set_acl = ext4_set_acl,
4096 };
Linux with added FPC-III support