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
53static struct buffer_head *ext4_append(handle_t *handle,
54 struct inode *inode,
55 ext4_lblk_t *block)
56{
57 struct ext4_map_blocks map;
58 struct buffer_head *bh;
59 int err;
60
61 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
62 ((inode->i_size >> 10) >=
63 EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
64 return ERR_PTR(error: -ENOSPC);
65
66 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
67 map.m_lblk = *block;
68 map.m_len = 1;
69
70 /*
71 * We're appending new directory block. Make sure the block is not
72 * allocated yet, otherwise we will end up corrupting the
73 * directory.
74 */
75 err = ext4_map_blocks(NULL, inode, map: &map, flags: 0);
76 if (err < 0)
77 return ERR_PTR(error: err);
78 if (err) {
79 EXT4_ERROR_INODE(inode, "Logical block already allocated");
80 return ERR_PTR(error: -EFSCORRUPTED);
81 }
82
83 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE);
84 if (IS_ERR(ptr: bh))
85 return bh;
86 inode->i_size += inode->i_sb->s_blocksize;
87 EXT4_I(inode)->i_disksize = inode->i_size;
88 err = ext4_mark_inode_dirty(handle, inode);
89 if (err)
90 goto out;
91 BUFFER_TRACE(bh, "get_write_access");
92 err = ext4_journal_get_write_access(handle, inode->i_sb, bh,
93 EXT4_JTR_NONE);
94 if (err)
95 goto out;
96 return bh;
97
98out:
99 brelse(bh);
100 ext4_std_error(inode->i_sb, err);
101 return ERR_PTR(error: err);
102}
103
104static int ext4_dx_csum_verify(struct inode *inode,
105 struct ext4_dir_entry *dirent);
106
107/*
108 * Hints to ext4_read_dirblock regarding whether we expect a directory
109 * block being read to be an index block, or a block containing
110 * directory entries (and if the latter, whether it was found via a
111 * logical block in an htree index block). This is used to control
112 * what sort of sanity checkinig ext4_read_dirblock() will do on the
113 * directory block read from the storage device. EITHER will means
114 * the caller doesn't know what kind of directory block will be read,
115 * so no specific verification will be done.
116 */
117typedef enum {
118 EITHER, INDEX, DIRENT, DIRENT_HTREE
119} dirblock_type_t;
120
121#define ext4_read_dirblock(inode, block, type) \
122 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__)
123
124static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
125 ext4_lblk_t block,
126 dirblock_type_t type,
127 const char *func,
128 unsigned int line)
129{
130 struct buffer_head *bh;
131 struct ext4_dir_entry *dirent;
132 int is_dx_block = 0;
133
134 if (block >= inode->i_size >> inode->i_blkbits) {
135 ext4_error_inode(inode, func, line, block,
136 "Attempting to read directory block (%u) that is past i_size (%llu)",
137 block, inode->i_size);
138 return ERR_PTR(error: -EFSCORRUPTED);
139 }
140
141 if (ext4_simulate_fail(sb: inode->i_sb, EXT4_SIM_DIRBLOCK_EIO))
142 bh = ERR_PTR(error: -EIO);
143 else
144 bh = ext4_bread(NULL, inode, block, 0);
145 if (IS_ERR(ptr: bh)) {
146 __ext4_warning(inode->i_sb, func, line,
147 "inode #%lu: lblock %lu: comm %s: "
148 "error %ld reading directory block",
149 inode->i_ino, (unsigned long)block,
150 current->comm, PTR_ERR(ptr: bh));
151
152 return bh;
153 }
154 /* The first directory block must not be a hole. */
155 if (!bh && (type == INDEX || type == DIRENT_HTREE || block == 0)) {
156 ext4_error_inode(inode, func, line, block,
157 "Directory hole found for htree %s block %u",
158 (type == INDEX) ? "index" : "leaf", block);
159 return ERR_PTR(error: -EFSCORRUPTED);
160 }
161 if (!bh)
162 return NULL;
163 dirent = (struct ext4_dir_entry *) bh->b_data;
164 /* Determine whether or not we have an index block */
165 if (is_dx(inode)) {
166 if (block == 0)
167 is_dx_block = 1;
168 else if (ext4_rec_len_from_disk(dlen: dirent->rec_len,
169 blocksize: inode->i_sb->s_blocksize) ==
170 inode->i_sb->s_blocksize)
171 is_dx_block = 1;
172 }
173 if (!is_dx_block && type == INDEX) {
174 ext4_error_inode(inode, func, line, block,
175 "directory leaf block found instead of index block");
176 brelse(bh);
177 return ERR_PTR(error: -EFSCORRUPTED);
178 }
179 if (!ext4_has_feature_metadata_csum(sb: inode->i_sb) ||
180 buffer_verified(bh))
181 return bh;
182
183 /*
184 * An empty leaf block can get mistaken for a index block; for
185 * this reason, we can only check the index checksum when the
186 * caller is sure it should be an index block.
187 */
188 if (is_dx_block && type == INDEX) {
189 if (ext4_dx_csum_verify(inode, dirent) &&
190 !ext4_simulate_fail(sb: inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))
191 set_buffer_verified(bh);
192 else {
193 ext4_error_inode_err(inode, func, line, block,
194 EFSBADCRC,
195 "Directory index failed checksum");
196 brelse(bh);
197 return ERR_PTR(error: -EFSBADCRC);
198 }
199 }
200 if (!is_dx_block) {
201 if (ext4_dirblock_csum_verify(inode, bh) &&
202 !ext4_simulate_fail(sb: inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))
203 set_buffer_verified(bh);
204 else {
205 ext4_error_inode_err(inode, func, line, block,
206 EFSBADCRC,
207 "Directory block failed checksum");
208 brelse(bh);
209 return ERR_PTR(error: -EFSBADCRC);
210 }
211 }
212 return bh;
213}
214
215#ifdef DX_DEBUG
216#define dxtrace(command) command
217#else
218#define dxtrace(command)
219#endif
220
221struct fake_dirent
222{
223 __le32 inode;
224 __le16 rec_len;
225 u8 name_len;
226 u8 file_type;
227};
228
229struct dx_countlimit
230{
231 __le16 limit;
232 __le16 count;
233};
234
235struct dx_entry
236{
237 __le32 hash;
238 __le32 block;
239};
240
241/*
242 * dx_root_info is laid out so that if it should somehow get overlaid by a
243 * dirent the two low bits of the hash version will be zero. Therefore, the
244 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
245 */
246
247struct dx_root
248{
249 struct fake_dirent dot;
250 char dot_name[4];
251 struct fake_dirent dotdot;
252 char dotdot_name[4];
253 struct dx_root_info
254 {
255 __le32 reserved_zero;
256 u8 hash_version;
257 u8 info_length; /* 8 */
258 u8 indirect_levels;
259 u8 unused_flags;
260 }
261 info;
262 struct dx_entry entries[];
263};
264
265struct dx_node
266{
267 struct fake_dirent fake;
268 struct dx_entry entries[];
269};
270
271
272struct dx_frame
273{
274 struct buffer_head *bh;
275 struct dx_entry *entries;
276 struct dx_entry *at;
277};
278
279struct dx_map_entry
280{
281 u32 hash;
282 u16 offs;
283 u16 size;
284};
285
286/*
287 * This goes at the end of each htree block.
288 */
289struct dx_tail {
290 u32 dt_reserved;
291 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
292};
293
294static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
295 struct ext4_filename *fname,
296 struct ext4_dir_entry_2 **res_dir);
297static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
298 struct inode *dir, struct inode *inode);
299
300/* checksumming functions */
301void ext4_initialize_dirent_tail(struct buffer_head *bh,
302 unsigned int blocksize)
303{
304 struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
305
306 memset(s: t, c: 0, n: sizeof(struct ext4_dir_entry_tail));
307 t->det_rec_len = ext4_rec_len_to_disk(
308 len: sizeof(struct ext4_dir_entry_tail), blocksize);
309 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
310}
311
312/* Walk through a dirent block to find a checksum "dirent" at the tail */
313static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
314 struct buffer_head *bh)
315{
316 struct ext4_dir_entry_tail *t;
317 int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
318
319#ifdef PARANOID
320 struct ext4_dir_entry *d, *top;
321
322 d = (struct ext4_dir_entry *)bh->b_data;
323 top = (struct ext4_dir_entry *)(bh->b_data +
324 (blocksize - sizeof(struct ext4_dir_entry_tail)));
325 while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
326 d = (struct ext4_dir_entry *)(((void *)d) +
327 ext4_rec_len_from_disk(d->rec_len, blocksize));
328
329 if (d != top)
330 return NULL;
331
332 t = (struct ext4_dir_entry_tail *)d;
333#else
334 t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb));
335#endif
336
337 if (t->det_reserved_zero1 ||
338 (ext4_rec_len_from_disk(dlen: t->det_rec_len, blocksize) !=
339 sizeof(struct ext4_dir_entry_tail)) ||
340 t->det_reserved_zero2 ||
341 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
342 return NULL;
343
344 return t;
345}
346
347static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size)
348{
349 struct ext4_inode_info *ei = EXT4_I(inode);
350 __u32 csum;
351
352 csum = ext4_chksum(crc: ei->i_csum_seed, address: (__u8 *)dirent, length: size);
353 return cpu_to_le32(csum);
354}
355
356#define warn_no_space_for_csum(inode) \
357 __warn_no_space_for_csum((inode), __func__, __LINE__)
358
359static void __warn_no_space_for_csum(struct inode *inode, const char *func,
360 unsigned int line)
361{
362 __ext4_warning_inode(inode, function: func, line,
363 fmt: "No space for directory leaf checksum. Please run e2fsck -D.");
364}
365
366int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)
367{
368 struct ext4_dir_entry_tail *t;
369
370 if (!ext4_has_feature_metadata_csum(sb: inode->i_sb))
371 return 1;
372
373 t = get_dirent_tail(inode, bh);
374 if (!t) {
375 warn_no_space_for_csum(inode);
376 return 0;
377 }
378
379 if (t->det_checksum != ext4_dirblock_csum(inode, dirent: bh->b_data,
380 size: (char *)t - bh->b_data))
381 return 0;
382
383 return 1;
384}
385
386static void ext4_dirblock_csum_set(struct inode *inode,
387 struct buffer_head *bh)
388{
389 struct ext4_dir_entry_tail *t;
390
391 if (!ext4_has_feature_metadata_csum(sb: inode->i_sb))
392 return;
393
394 t = get_dirent_tail(inode, bh);
395 if (!t) {
396 warn_no_space_for_csum(inode);
397 return;
398 }
399
400 t->det_checksum = ext4_dirblock_csum(inode, dirent: bh->b_data,
401 size: (char *)t - bh->b_data);
402}
403
404int ext4_handle_dirty_dirblock(handle_t *handle,
405 struct inode *inode,
406 struct buffer_head *bh)
407{
408 ext4_dirblock_csum_set(inode, bh);
409 return ext4_handle_dirty_metadata(handle, inode, bh);
410}
411
412static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
413 struct ext4_dir_entry *dirent,
414 int *offset)
415{
416 struct ext4_dir_entry *dp;
417 struct dx_root_info *root;
418 int count_offset;
419 int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
420 unsigned int rlen = ext4_rec_len_from_disk(dlen: dirent->rec_len, blocksize);
421
422 if (rlen == blocksize)
423 count_offset = 8;
424 else if (rlen == 12) {
425 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
426 if (ext4_rec_len_from_disk(dlen: dp->rec_len, blocksize) != blocksize - 12)
427 return NULL;
428 root = (struct dx_root_info *)(((void *)dp + 12));
429 if (root->reserved_zero ||
430 root->info_length != sizeof(struct dx_root_info))
431 return NULL;
432 count_offset = 32;
433 } else
434 return NULL;
435
436 if (offset)
437 *offset = count_offset;
438 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
439}
440
441static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
442 int count_offset, int count, struct dx_tail *t)
443{
444 struct ext4_inode_info *ei = EXT4_I(inode);
445 __u32 csum;
446 int size;
447 __u32 dummy_csum = 0;
448 int offset = offsetof(struct dx_tail, dt_checksum);
449
450 size = count_offset + (count * sizeof(struct dx_entry));
451 csum = ext4_chksum(crc: ei->i_csum_seed, address: (__u8 *)dirent, length: size);
452 csum = ext4_chksum(crc: csum, address: (__u8 *)t, length: offset);
453 csum = ext4_chksum(crc: csum, address: (__u8 *)&dummy_csum, length: sizeof(dummy_csum));
454
455 return cpu_to_le32(csum);
456}
457
458static int ext4_dx_csum_verify(struct inode *inode,
459 struct ext4_dir_entry *dirent)
460{
461 struct dx_countlimit *c;
462 struct dx_tail *t;
463 int count_offset, limit, count;
464
465 if (!ext4_has_feature_metadata_csum(sb: inode->i_sb))
466 return 1;
467
468 c = get_dx_countlimit(inode, dirent, offset: &count_offset);
469 if (!c) {
470 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
471 return 0;
472 }
473 limit = le16_to_cpu(c->limit);
474 count = le16_to_cpu(c->count);
475 if (count_offset + (limit * sizeof(struct dx_entry)) >
476 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
477 warn_no_space_for_csum(inode);
478 return 0;
479 }
480 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
481
482 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
483 count, t))
484 return 0;
485 return 1;
486}
487
488static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
489{
490 struct dx_countlimit *c;
491 struct dx_tail *t;
492 int count_offset, limit, count;
493
494 if (!ext4_has_feature_metadata_csum(sb: inode->i_sb))
495 return;
496
497 c = get_dx_countlimit(inode, dirent, offset: &count_offset);
498 if (!c) {
499 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
500 return;
501 }
502 limit = le16_to_cpu(c->limit);
503 count = le16_to_cpu(c->count);
504 if (count_offset + (limit * sizeof(struct dx_entry)) >
505 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
506 warn_no_space_for_csum(inode);
507 return;
508 }
509 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
510
511 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
512}
513
514static inline int ext4_handle_dirty_dx_node(handle_t *handle,
515 struct inode *inode,
516 struct buffer_head *bh)
517{
518 ext4_dx_csum_set(inode, dirent: (struct ext4_dir_entry *)bh->b_data);
519 return ext4_handle_dirty_metadata(handle, inode, bh);
520}
521
522/*
523 * p is at least 6 bytes before the end of page
524 */
525static inline struct ext4_dir_entry_2 *
526ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
527{
528 return (struct ext4_dir_entry_2 *)((char *)p +
529 ext4_rec_len_from_disk(dlen: p->rec_len, blocksize));
530}
531
532/*
533 * Future: use high four bits of block for coalesce-on-delete flags
534 * Mask them off for now.
535 */
536
537static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
538{
539 return le32_to_cpu(entry->block) & 0x0fffffff;
540}
541
542static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
543{
544 entry->block = cpu_to_le32(value);
545}
546
547static inline unsigned dx_get_hash(struct dx_entry *entry)
548{
549 return le32_to_cpu(entry->hash);
550}
551
552static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
553{
554 entry->hash = cpu_to_le32(value);
555}
556
557static inline unsigned dx_get_count(struct dx_entry *entries)
558{
559 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
560}
561
562static inline unsigned dx_get_limit(struct dx_entry *entries)
563{
564 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
565}
566
567static inline void dx_set_count(struct dx_entry *entries, unsigned value)
568{
569 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
570}
571
572static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
573{
574 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
575}
576
577static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
578{
579 unsigned int entry_space = dir->i_sb->s_blocksize -
580 ext4_dir_rec_len(name_len: 1, NULL) -
581 ext4_dir_rec_len(name_len: 2, NULL) - infosize;
582
583 if (ext4_has_feature_metadata_csum(sb: dir->i_sb))
584 entry_space -= sizeof(struct dx_tail);
585 return entry_space / sizeof(struct dx_entry);
586}
587
588static inline unsigned dx_node_limit(struct inode *dir)
589{
590 unsigned int entry_space = dir->i_sb->s_blocksize -
591 ext4_dir_rec_len(name_len: 0, dir);
592
593 if (ext4_has_feature_metadata_csum(sb: 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
602static 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
614struct stats
615{
616 unsigned names;
617 unsigned space;
618 unsigned bcount;
619};
620
621static 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 /* Directory is not encrypted */
648 (void) ext4fs_dirhash(dir, de->name,
649 de->name_len, &h);
650 printk("%*.s:(U)%x.%u ", len,
651 name, h.hash,
652 (unsigned) ((char *) de
653 - base));
654 } else {
655 struct fscrypt_str de_name =
656 FSTR_INIT(name, len);
657
658 /* Directory is encrypted */
659 res = fscrypt_fname_alloc_buffer(
660 len, &fname_crypto_str);
661 if (res)
662 printk(KERN_WARNING "Error "
663 "allocating crypto "
664 "buffer--skipping "
665 "crypto\n");
666 res = fscrypt_fname_disk_to_usr(dir,
667 0, 0, &de_name,
668 &fname_crypto_str);
669 if (res) {
670 printk(KERN_WARNING "Error "
671 "converting filename "
672 "from disk to usr"
673 "\n");
674 name = "??";
675 len = 2;
676 } else {
677 name = fname_crypto_str.name;
678 len = fname_crypto_str.len;
679 }
680 if (IS_CASEFOLDED(dir))
681 h.hash = EXT4_DIRENT_HASH(de);
682 else
683 (void) ext4fs_dirhash(dir,
684 de->name,
685 de->name_len, &h);
686 printk("%*.s:(E)%x.%u ", len, name,
687 h.hash, (unsigned) ((char *) de
688 - base));
689 fscrypt_fname_free_buffer(
690 &fname_crypto_str);
691 }
692#else
693 int len = de->name_len;
694 char *name = de->name;
695 (void) ext4fs_dirhash(dir, de->name,
696 de->name_len, &h);
697 printk("%*.s:%x.%u ", len, name, h.hash,
698 (unsigned) ((char *) de - base));
699#endif
700 }
701 space += ext4_dir_rec_len(de->name_len, dir);
702 names++;
703 }
704 de = ext4_next_entry(de, size);
705 }
706 printk(KERN_CONT "(%i)\n", names);
707 return (struct stats) { names, space, 1 };
708}
709
710struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
711 struct dx_entry *entries, int levels)
712{
713 unsigned blocksize = dir->i_sb->s_blocksize;
714 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
715 unsigned bcount = 0;
716 struct buffer_head *bh;
717 printk("%i indexed blocks...\n", count);
718 for (i = 0; i < count; i++, entries++)
719 {
720 ext4_lblk_t block = dx_get_block(entries);
721 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
722 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
723 struct stats stats;
724 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
725 bh = ext4_bread(NULL,dir, block, 0);
726 if (!bh || IS_ERR(bh))
727 continue;
728 stats = levels?
729 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
730 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)
731 bh->b_data, blocksize, 0);
732 names += stats.names;
733 space += stats.space;
734 bcount += stats.bcount;
735 brelse(bh);
736 }
737 if (bcount)
738 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
739 levels ? "" : " ", names, space/bcount,
740 (space/bcount)*100/blocksize);
741 return (struct stats) { names, space, bcount};
742}
743
744/*
745 * Linear search cross check
746 */
747static inline void htree_rep_invariant_check(struct dx_entry *at,
748 struct dx_entry *target,
749 u32 hash, unsigned int n)
750{
751 while (n--) {
752 dxtrace(printk(KERN_CONT ","));
753 if (dx_get_hash(++at) > hash) {
754 at--;
755 break;
756 }
757 }
758 ASSERT(at == target - 1);
759}
760#else /* DX_DEBUG */
761static inline void htree_rep_invariant_check(struct dx_entry *at,
762 struct dx_entry *target,
763 u32 hash, unsigned int n)
764{
765}
766#endif /* DX_DEBUG */
767
768/*
769 * Probe for a directory leaf block to search.
770 *
771 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
772 * error in the directory index, and the caller should fall back to
773 * searching the directory normally. The callers of dx_probe **MUST**
774 * check for this error code, and make sure it never gets reflected
775 * back to userspace.
776 */
777static struct dx_frame *
778dx_probe(struct ext4_filename *fname, struct inode *dir,
779 struct dx_hash_info *hinfo, struct dx_frame *frame_in)
780{
781 unsigned count, indirect, level, i;
782 struct dx_entry *at, *entries, *p, *q, *m;
783 struct dx_root *root;
784 struct dx_frame *frame = frame_in;
785 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);
786 u32 hash;
787 ext4_lblk_t block;
788 ext4_lblk_t blocks[EXT4_HTREE_LEVEL];
789
790 memset(s: frame_in, c: 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0]));
791 frame->bh = ext4_read_dirblock(dir, 0, INDEX);
792 if (IS_ERR(ptr: frame->bh))
793 return (struct dx_frame *) frame->bh;
794
795 root = (struct dx_root *) frame->bh->b_data;
796 if (root->info.hash_version != DX_HASH_TEA &&
797 root->info.hash_version != DX_HASH_HALF_MD4 &&
798 root->info.hash_version != DX_HASH_LEGACY &&
799 root->info.hash_version != DX_HASH_SIPHASH) {
800 ext4_warning_inode(dir, "Unrecognised inode hash code %u",
801 root->info.hash_version);
802 goto fail;
803 }
804 if (ext4_hash_in_dirent(inode: dir)) {
805 if (root->info.hash_version != DX_HASH_SIPHASH) {
806 ext4_warning_inode(dir,
807 "Hash in dirent, but hash is not SIPHASH");
808 goto fail;
809 }
810 } else {
811 if (root->info.hash_version == DX_HASH_SIPHASH) {
812 ext4_warning_inode(dir,
813 "Hash code is SIPHASH, but hash not in dirent");
814 goto fail;
815 }
816 }
817 if (fname)
818 hinfo = &fname->hinfo;
819 hinfo->hash_version = root->info.hash_version;
820 if (hinfo->hash_version <= DX_HASH_TEA)
821 hinfo->hash_version += EXT4_SB(sb: dir->i_sb)->s_hash_unsigned;
822 hinfo->seed = EXT4_SB(sb: dir->i_sb)->s_hash_seed;
823 /* hash is already computed for encrypted casefolded directory */
824 if (fname && fname_name(fname) &&
825 !(IS_ENCRYPTED(dir) && IS_CASEFOLDED(dir))) {
826 int ret = ext4fs_dirhash(dir, fname_name(fname),
827 fname_len(fname), hinfo);
828 if (ret < 0) {
829 ret_err = ERR_PTR(error: ret);
830 goto fail;
831 }
832 }
833 hash = hinfo->hash;
834
835 if (root->info.unused_flags & 1) {
836 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x",
837 root->info.unused_flags);
838 goto fail;
839 }
840
841 indirect = root->info.indirect_levels;
842 if (indirect >= ext4_dir_htree_level(sb: dir->i_sb)) {
843 ext4_warning(dir->i_sb,
844 "Directory (ino: %lu) htree depth %#06x exceed"
845 "supported value", dir->i_ino,
846 ext4_dir_htree_level(dir->i_sb));
847 if (ext4_dir_htree_level(sb: dir->i_sb) < EXT4_HTREE_LEVEL) {
848 ext4_warning(dir->i_sb, "Enable large directory "
849 "feature to access it");
850 }
851 goto fail;
852 }
853
854 entries = (struct dx_entry *)(((char *)&root->info) +
855 root->info.info_length);
856
857 if (dx_get_limit(entries) != dx_root_limit(dir,
858 infosize: root->info.info_length)) {
859 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
860 dx_get_limit(entries),
861 dx_root_limit(dir, root->info.info_length));
862 goto fail;
863 }
864
865 dxtrace(printk("Look up %x", hash));
866 level = 0;
867 blocks[0] = 0;
868 while (1) {
869 count = dx_get_count(entries);
870 if (!count || count > dx_get_limit(entries)) {
871 ext4_warning_inode(dir,
872 "dx entry: count %u beyond limit %u",
873 count, dx_get_limit(entries));
874 goto fail;
875 }
876
877 p = entries + 1;
878 q = entries + count - 1;
879 while (p <= q) {
880 m = p + (q - p) / 2;
881 dxtrace(printk(KERN_CONT "."));
882 if (dx_get_hash(entry: m) > hash)
883 q = m - 1;
884 else
885 p = m + 1;
886 }
887
888 htree_rep_invariant_check(at: entries, target: p, hash, n: count - 1);
889
890 at = p - 1;
891 dxtrace(printk(KERN_CONT " %x->%u\n",
892 at == entries ? 0 : dx_get_hash(at),
893 dx_get_block(at)));
894 frame->entries = entries;
895 frame->at = at;
896
897 block = dx_get_block(entry: at);
898 for (i = 0; i <= level; i++) {
899 if (blocks[i] == block) {
900 ext4_warning_inode(dir,
901 "dx entry: tree cycle block %u points back to block %u",
902 blocks[level], block);
903 goto fail;
904 }
905 }
906 if (++level > indirect)
907 return frame;
908 blocks[level] = block;
909 frame++;
910 frame->bh = ext4_read_dirblock(dir, block, INDEX);
911 if (IS_ERR(ptr: frame->bh)) {
912 ret_err = (struct dx_frame *) frame->bh;
913 frame->bh = NULL;
914 goto fail;
915 }
916
917 entries = ((struct dx_node *) frame->bh->b_data)->entries;
918
919 if (dx_get_limit(entries) != dx_node_limit(dir)) {
920 ext4_warning_inode(dir,
921 "dx entry: limit %u != node limit %u",
922 dx_get_limit(entries), dx_node_limit(dir));
923 goto fail;
924 }
925 }
926fail:
927 while (frame >= frame_in) {
928 brelse(bh: frame->bh);
929 frame--;
930 }
931
932 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
933 ext4_warning_inode(dir,
934 "Corrupt directory, running e2fsck is recommended");
935 return ret_err;
936}
937
938static void dx_release(struct dx_frame *frames)
939{
940 struct dx_root_info *info;
941 int i;
942 unsigned int indirect_levels;
943
944 if (frames[0].bh == NULL)
945 return;
946
947 info = &((struct dx_root *)frames[0].bh->b_data)->info;
948 /* save local copy, "info" may be freed after brelse() */
949 indirect_levels = info->indirect_levels;
950 for (i = 0; i <= indirect_levels; i++) {
951 if (frames[i].bh == NULL)
952 break;
953 brelse(bh: frames[i].bh);
954 frames[i].bh = NULL;
955 }
956}
957
958/*
959 * This function increments the frame pointer to search the next leaf
960 * block, and reads in the necessary intervening nodes if the search
961 * should be necessary. Whether or not the search is necessary is
962 * controlled by the hash parameter. If the hash value is even, then
963 * the search is only continued if the next block starts with that
964 * hash value. This is used if we are searching for a specific file.
965 *
966 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
967 *
968 * This function returns 1 if the caller should continue to search,
969 * or 0 if it should not. If there is an error reading one of the
970 * index blocks, it will a negative error code.
971 *
972 * If start_hash is non-null, it will be filled in with the starting
973 * hash of the next page.
974 */
975static int ext4_htree_next_block(struct inode *dir, __u32 hash,
976 struct dx_frame *frame,
977 struct dx_frame *frames,
978 __u32 *start_hash)
979{
980 struct dx_frame *p;
981 struct buffer_head *bh;
982 int num_frames = 0;
983 __u32 bhash;
984
985 p = frame;
986 /*
987 * Find the next leaf page by incrementing the frame pointer.
988 * If we run out of entries in the interior node, loop around and
989 * increment pointer in the parent node. When we break out of
990 * this loop, num_frames indicates the number of interior
991 * nodes need to be read.
992 */
993 while (1) {
994 if (++(p->at) < p->entries + dx_get_count(entries: p->entries))
995 break;
996 if (p == frames)
997 return 0;
998 num_frames++;
999 p--;
1000 }
1001
1002 /*
1003 * If the hash is 1, then continue only if the next page has a
1004 * continuation hash of any value. This is used for readdir
1005 * handling. Otherwise, check to see if the hash matches the
1006 * desired continuation hash. If it doesn't, return since
1007 * there's no point to read in the successive index pages.
1008 */
1009 bhash = dx_get_hash(entry: p->at);
1010 if (start_hash)
1011 *start_hash = bhash;
1012 if ((hash & 1) == 0) {
1013 if ((bhash & ~1) != hash)
1014 return 0;
1015 }
1016 /*
1017 * If the hash is HASH_NB_ALWAYS, we always go to the next
1018 * block so no check is necessary
1019 */
1020 while (num_frames--) {
1021 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
1022 if (IS_ERR(ptr: bh))
1023 return PTR_ERR(ptr: bh);
1024 p++;
1025 brelse(bh: p->bh);
1026 p->bh = bh;
1027 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
1028 }
1029 return 1;
1030}
1031
1032
1033/*
1034 * This function fills a red-black tree with information from a
1035 * directory block. It returns the number directory entries loaded
1036 * into the tree. If there is an error it is returned in err.
1037 */
1038static int htree_dirblock_to_tree(struct file *dir_file,
1039 struct inode *dir, ext4_lblk_t block,
1040 struct dx_hash_info *hinfo,
1041 __u32 start_hash, __u32 start_minor_hash)
1042{
1043 struct buffer_head *bh;
1044 struct ext4_dir_entry_2 *de, *top;
1045 int err = 0, count = 0;
1046 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;
1047 int csum = ext4_has_feature_metadata_csum(sb: dir->i_sb);
1048
1049 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
1050 (unsigned long)block));
1051 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
1052 if (IS_ERR(ptr: bh))
1053 return PTR_ERR(ptr: bh);
1054
1055 de = (struct ext4_dir_entry_2 *) bh->b_data;
1056 /* csum entries are not larger in the casefolded encrypted case */
1057 top = (struct ext4_dir_entry_2 *) ((char *) de +
1058 dir->i_sb->s_blocksize -
1059 ext4_dir_rec_len(name_len: 0,
1060 dir: csum ? NULL : dir));
1061 /* Check if the directory is encrypted */
1062 if (IS_ENCRYPTED(dir)) {
1063 err = fscrypt_prepare_readdir(dir);
1064 if (err < 0) {
1065 brelse(bh);
1066 return err;
1067 }
1068 err = fscrypt_fname_alloc_buffer(EXT4_NAME_LEN,
1069 crypto_str: &fname_crypto_str);
1070 if (err < 0) {
1071 brelse(bh);
1072 return err;
1073 }
1074 }
1075
1076 for (; de < top; de = ext4_next_entry(p: de, blocksize: dir->i_sb->s_blocksize)) {
1077 if (ext4_check_dir_entry(dir, NULL, de, bh,
1078 bh->b_data, bh->b_size,
1079 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
1080 + ((char *)de - bh->b_data))) {
1081 /* silently ignore the rest of the block */
1082 break;
1083 }
1084 if (ext4_hash_in_dirent(inode: dir)) {
1085 if (de->name_len && de->inode) {
1086 hinfo->hash = EXT4_DIRENT_HASH(de);
1087 hinfo->minor_hash = EXT4_DIRENT_MINOR_HASH(de);
1088 } else {
1089 hinfo->hash = 0;
1090 hinfo->minor_hash = 0;
1091 }
1092 } else {
1093 err = ext4fs_dirhash(dir, name: de->name,
1094 len: de->name_len, hinfo);
1095 if (err < 0) {
1096 count = err;
1097 goto errout;
1098 }
1099 }
1100 if ((hinfo->hash < start_hash) ||
1101 ((hinfo->hash == start_hash) &&
1102 (hinfo->minor_hash < start_minor_hash)))
1103 continue;
1104 if (de->inode == 0)
1105 continue;
1106 if (!IS_ENCRYPTED(dir)) {
1107 tmp_str.name = de->name;
1108 tmp_str.len = de->name_len;
1109 err = ext4_htree_store_dirent(dir_file,
1110 hash: hinfo->hash, minor_hash: hinfo->minor_hash, dirent: de,
1111 ent_name: &tmp_str);
1112 } else {
1113 int save_len = fname_crypto_str.len;
1114 struct fscrypt_str de_name = FSTR_INIT(de->name,
1115 de->name_len);
1116
1117 /* Directory is encrypted */
1118 err = fscrypt_fname_disk_to_usr(inode: dir, hash: hinfo->hash,
1119 minor_hash: hinfo->minor_hash, iname: &de_name,
1120 oname: &fname_crypto_str);
1121 if (err) {
1122 count = err;
1123 goto errout;
1124 }
1125 err = ext4_htree_store_dirent(dir_file,
1126 hash: hinfo->hash, minor_hash: hinfo->minor_hash, dirent: de,
1127 ent_name: &fname_crypto_str);
1128 fname_crypto_str.len = save_len;
1129 }
1130 if (err != 0) {
1131 count = err;
1132 goto errout;
1133 }
1134 count++;
1135 }
1136errout:
1137 brelse(bh);
1138 fscrypt_fname_free_buffer(crypto_str: &fname_crypto_str);
1139 return count;
1140}
1141
1142
1143/*
1144 * This function fills a red-black tree with information from a
1145 * directory. We start scanning the directory in hash order, starting
1146 * at start_hash and start_minor_hash.
1147 *
1148 * This function returns the number of entries inserted into the tree,
1149 * or a negative error code.
1150 */
1151int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1152 __u32 start_minor_hash, __u32 *next_hash)
1153{
1154 struct dx_hash_info hinfo;
1155 struct ext4_dir_entry_2 *de;
1156 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1157 struct inode *dir;
1158 ext4_lblk_t block;
1159 int count = 0;
1160 int ret, err;
1161 __u32 hashval;
1162 struct fscrypt_str tmp_str;
1163
1164 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
1165 start_hash, start_minor_hash));
1166 dir = file_inode(f: dir_file);
1167 if (!(ext4_test_inode_flag(inode: dir, bit: EXT4_INODE_INDEX))) {
1168 if (ext4_hash_in_dirent(inode: dir))
1169 hinfo.hash_version = DX_HASH_SIPHASH;
1170 else
1171 hinfo.hash_version =
1172 EXT4_SB(sb: dir->i_sb)->s_def_hash_version;
1173 if (hinfo.hash_version <= DX_HASH_TEA)
1174 hinfo.hash_version +=
1175 EXT4_SB(sb: dir->i_sb)->s_hash_unsigned;
1176 hinfo.seed = EXT4_SB(sb: dir->i_sb)->s_hash_seed;
1177 if (ext4_has_inline_data(inode: dir)) {
1178 int has_inline_data = 1;
1179 count = ext4_inlinedir_to_tree(dir_file, dir, block: 0,
1180 hinfo: &hinfo, start_hash,
1181 start_minor_hash,
1182 has_inline_data: &has_inline_data);
1183 if (has_inline_data) {
1184 *next_hash = ~0;
1185 return count;
1186 }
1187 }
1188 count = htree_dirblock_to_tree(dir_file, dir, block: 0, hinfo: &hinfo,
1189 start_hash, start_minor_hash);
1190 *next_hash = ~0;
1191 return count;
1192 }
1193 hinfo.hash = start_hash;
1194 hinfo.minor_hash = 0;
1195 frame = dx_probe(NULL, dir, hinfo: &hinfo, frame_in: frames);
1196 if (IS_ERR(ptr: frame))
1197 return PTR_ERR(ptr: frame);
1198
1199 /* Add '.' and '..' from the htree header */
1200 if (!start_hash && !start_minor_hash) {
1201 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1202 tmp_str.name = de->name;
1203 tmp_str.len = de->name_len;
1204 err = ext4_htree_store_dirent(dir_file, hash: 0, minor_hash: 0,
1205 dirent: de, ent_name: &tmp_str);
1206 if (err != 0)
1207 goto errout;
1208 count++;
1209 }
1210 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
1211 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1212 de = ext4_next_entry(p: de, blocksize: dir->i_sb->s_blocksize);
1213 tmp_str.name = de->name;
1214 tmp_str.len = de->name_len;
1215 err = ext4_htree_store_dirent(dir_file, hash: 2, minor_hash: 0,
1216 dirent: de, ent_name: &tmp_str);
1217 if (err != 0)
1218 goto errout;
1219 count++;
1220 }
1221
1222 while (1) {
1223 if (fatal_signal_pending(current)) {
1224 err = -ERESTARTSYS;
1225 goto errout;
1226 }
1227 cond_resched();
1228 block = dx_get_block(entry: frame->at);
1229 ret = htree_dirblock_to_tree(dir_file, dir, block, hinfo: &hinfo,
1230 start_hash, start_minor_hash);
1231 if (ret < 0) {
1232 err = ret;
1233 goto errout;
1234 }
1235 count += ret;
1236 hashval = ~0;
1237 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
1238 frame, frames, start_hash: &hashval);
1239 *next_hash = hashval;
1240 if (ret < 0) {
1241 err = ret;
1242 goto errout;
1243 }
1244 /*
1245 * Stop if: (a) there are no more entries, or
1246 * (b) we have inserted at least one entry and the
1247 * next hash value is not a continuation
1248 */
1249 if ((ret == 0) ||
1250 (count && ((hashval & 1) == 0)))
1251 break;
1252 }
1253 dx_release(frames);
1254 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1255 "next hash: %x\n", count, *next_hash));
1256 return count;
1257errout:
1258 dx_release(frames);
1259 return (err);
1260}
1261
1262static inline int search_dirblock(struct buffer_head *bh,
1263 struct inode *dir,
1264 struct ext4_filename *fname,
1265 unsigned int offset,
1266 struct ext4_dir_entry_2 **res_dir)
1267{
1268 return ext4_search_dir(bh, search_buf: bh->b_data, buf_size: dir->i_sb->s_blocksize, dir,
1269 fname, offset, res_dir);
1270}
1271
1272/*
1273 * Directory block splitting, compacting
1274 */
1275
1276/*
1277 * Create map of hash values, offsets, and sizes, stored at end of block.
1278 * Returns number of entries mapped.
1279 */
1280static int dx_make_map(struct inode *dir, struct buffer_head *bh,
1281 struct dx_hash_info *hinfo,
1282 struct dx_map_entry *map_tail)
1283{
1284 int count = 0;
1285 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)bh->b_data;
1286 unsigned int buflen = bh->b_size;
1287 char *base = bh->b_data;
1288 struct dx_hash_info h = *hinfo;
1289 int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
1290
1291 if (ext4_has_feature_metadata_csum(sb: dir->i_sb))
1292 buflen -= sizeof(struct ext4_dir_entry_tail);
1293
1294 while ((char *) de < base + buflen) {
1295 if (ext4_check_dir_entry(dir, NULL, de, bh, base, buflen,
1296 ((char *)de) - base))
1297 return -EFSCORRUPTED;
1298 if (de->name_len && de->inode) {
1299 if (ext4_hash_in_dirent(inode: dir))
1300 h.hash = EXT4_DIRENT_HASH(de);
1301 else {
1302 int err = ext4fs_dirhash(dir, name: de->name,
1303 len: de->name_len, hinfo: &h);
1304 if (err < 0)
1305 return err;
1306 }
1307 map_tail--;
1308 map_tail->hash = h.hash;
1309 map_tail->offs = ((char *) de - base)>>2;
1310 map_tail->size = ext4_rec_len_from_disk(dlen: de->rec_len,
1311 blocksize);
1312 count++;
1313 cond_resched();
1314 }
1315 de = ext4_next_entry(p: de, blocksize);
1316 }
1317 return count;
1318}
1319
1320/* Sort map by hash value */
1321static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1322{
1323 struct dx_map_entry *p, *q, *top = map + count - 1;
1324 int more;
1325 /* Combsort until bubble sort doesn't suck */
1326 while (count > 2) {
1327 count = count*10/13;
1328 if (count - 9 < 2) /* 9, 10 -> 11 */
1329 count = 11;
1330 for (p = top, q = p - count; q >= map; p--, q--)
1331 if (p->hash < q->hash)
1332 swap(*p, *q);
1333 }
1334 /* Garden variety bubble sort */
1335 do {
1336 more = 0;
1337 q = top;
1338 while (q-- > map) {
1339 if (q[1].hash >= q[0].hash)
1340 continue;
1341 swap(*(q+1), *q);
1342 more = 1;
1343 }
1344 } while(more);
1345}
1346
1347static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
1348{
1349 struct dx_entry *entries = frame->entries;
1350 struct dx_entry *old = frame->at, *new = old + 1;
1351 int count = dx_get_count(entries);
1352
1353 ASSERT(count < dx_get_limit(entries));
1354 ASSERT(old < entries + count);
1355 memmove(dest: new + 1, src: new, count: (char *)(entries + count) - (char *)(new));
1356 dx_set_hash(entry: new, value: hash);
1357 dx_set_block(entry: new, value: block);
1358 dx_set_count(entries, value: count + 1);
1359}
1360
1361#if IS_ENABLED(CONFIG_UNICODE)
1362int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
1363 struct ext4_filename *name)
1364{
1365 struct qstr *cf_name = &name->cf_name;
1366 unsigned char *buf;
1367 struct dx_hash_info *hinfo = &name->hinfo;
1368 int len;
1369
1370 if (!IS_CASEFOLDED(dir) ||
1371 (IS_ENCRYPTED(dir) && !fscrypt_has_encryption_key(dir))) {
1372 cf_name->name = NULL;
1373 return 0;
1374 }
1375
1376 buf = kmalloc(EXT4_NAME_LEN, GFP_NOFS);
1377 if (!buf)
1378 return -ENOMEM;
1379
1380 len = utf8_casefold(dir->i_sb->s_encoding, iname, buf, EXT4_NAME_LEN);
1381 if (len <= 0) {
1382 kfree(buf);
1383 buf = NULL;
1384 }
1385 cf_name->name = buf;
1386 cf_name->len = (unsigned) len;
1387
1388 if (!IS_ENCRYPTED(dir))
1389 return 0;
1390
1391 hinfo->hash_version = DX_HASH_SIPHASH;
1392 hinfo->seed = NULL;
1393 if (cf_name->name)
1394 return ext4fs_dirhash(dir, cf_name->name, cf_name->len, hinfo);
1395 else
1396 return ext4fs_dirhash(dir, iname->name, iname->len, hinfo);
1397}
1398#endif
1399
1400/*
1401 * Test whether a directory entry matches the filename being searched for.
1402 *
1403 * Return: %true if the directory entry matches, otherwise %false.
1404 */
1405static bool ext4_match(struct inode *parent,
1406 const struct ext4_filename *fname,
1407 struct ext4_dir_entry_2 *de)
1408{
1409 struct fscrypt_name f;
1410
1411 if (!de->inode)
1412 return false;
1413
1414 f.usr_fname = fname->usr_fname;
1415 f.disk_name = fname->disk_name;
1416#ifdef CONFIG_FS_ENCRYPTION
1417 f.crypto_buf = fname->crypto_buf;
1418#endif
1419
1420#if IS_ENABLED(CONFIG_UNICODE)
1421 if (IS_CASEFOLDED(parent) &&
1422 (!IS_ENCRYPTED(parent) || fscrypt_has_encryption_key(parent))) {
1423 /*
1424 * Just checking IS_ENCRYPTED(parent) below is not
1425 * sufficient to decide whether one can use the hash for
1426 * skipping the string comparison, because the key might
1427 * have been added right after
1428 * ext4_fname_setup_ci_filename(). In this case, a hash
1429 * mismatch will be a false negative. Therefore, make
1430 * sure cf_name was properly initialized before
1431 * considering the calculated hash.
1432 */
1433 if (sb_no_casefold_compat_fallback(parent->i_sb) &&
1434 IS_ENCRYPTED(parent) && fname->cf_name.name &&
1435 (fname->hinfo.hash != EXT4_DIRENT_HASH(de) ||
1436 fname->hinfo.minor_hash != EXT4_DIRENT_MINOR_HASH(de)))
1437 return false;
1438 /*
1439 * Treat comparison errors as not a match. The
1440 * only case where it happens is on a disk
1441 * corruption or ENOMEM.
1442 */
1443
1444 return generic_ci_match(parent, fname->usr_fname,
1445 &fname->cf_name, de->name,
1446 de->name_len) > 0;
1447 }
1448#endif
1449
1450 return fscrypt_match_name(fname: &f, de_name: de->name, de_name_len: de->name_len);
1451}
1452
1453/*
1454 * Returns 0 if not found, -EFSCORRUPTED on failure, and 1 on success
1455 */
1456int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
1457 struct inode *dir, struct ext4_filename *fname,
1458 unsigned int offset, struct ext4_dir_entry_2 **res_dir)
1459{
1460 struct ext4_dir_entry_2 * de;
1461 char * dlimit;
1462 int de_len;
1463
1464 de = (struct ext4_dir_entry_2 *)search_buf;
1465 dlimit = search_buf + buf_size;
1466 while ((char *) de < dlimit - EXT4_BASE_DIR_LEN) {
1467 /* this code is executed quadratically often */
1468 /* do minimal checking `by hand' */
1469 if (de->name + de->name_len <= dlimit &&
1470 ext4_match(parent: dir, fname, de)) {
1471 /* found a match - just to be sure, do
1472 * a full check */
1473 if (ext4_check_dir_entry(dir, NULL, de, bh, search_buf,
1474 buf_size, offset))
1475 return -EFSCORRUPTED;
1476 *res_dir = de;
1477 return 1;
1478 }
1479 /* prevent looping on a bad block */
1480 de_len = ext4_rec_len_from_disk(dlen: de->rec_len,
1481 blocksize: dir->i_sb->s_blocksize);
1482 if (de_len <= 0)
1483 return -EFSCORRUPTED;
1484 offset += de_len;
1485 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1486 }
1487 return 0;
1488}
1489
1490static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1491 struct ext4_dir_entry *de)
1492{
1493 struct super_block *sb = dir->i_sb;
1494
1495 if (!is_dx(dir))
1496 return 0;
1497 if (block == 0)
1498 return 1;
1499 if (de->inode == 0 &&
1500 ext4_rec_len_from_disk(dlen: de->rec_len, blocksize: sb->s_blocksize) ==
1501 sb->s_blocksize)
1502 return 1;
1503 return 0;
1504}
1505
1506/*
1507 * __ext4_find_entry()
1508 *
1509 * finds an entry in the specified directory with the wanted name. It
1510 * returns the cache buffer in which the entry was found, and the entry
1511 * itself (as a parameter - res_dir). It does NOT read the inode of the
1512 * entry - you'll have to do that yourself if you want to.
1513 *
1514 * The returned buffer_head has ->b_count elevated. The caller is expected
1515 * to brelse() it when appropriate.
1516 */
1517static struct buffer_head *__ext4_find_entry(struct inode *dir,
1518 struct ext4_filename *fname,
1519 struct ext4_dir_entry_2 **res_dir,
1520 int *inlined)
1521{
1522 struct super_block *sb;
1523 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1524 struct buffer_head *bh, *ret = NULL;
1525 ext4_lblk_t start, block;
1526 const u8 *name = fname->usr_fname->name;
1527 size_t ra_max = 0; /* Number of bh's in the readahead
1528 buffer, bh_use[] */
1529 size_t ra_ptr = 0; /* Current index into readahead
1530 buffer */
1531 ext4_lblk_t nblocks;
1532 int i, namelen, retval;
1533
1534 *res_dir = NULL;
1535 sb = dir->i_sb;
1536 namelen = fname->usr_fname->len;
1537 if (namelen > EXT4_NAME_LEN)
1538 return NULL;
1539
1540 if (ext4_has_inline_data(inode: dir)) {
1541 int has_inline_data = 1;
1542 ret = ext4_find_inline_entry(dir, fname, res_dir,
1543 has_inline_data: &has_inline_data);
1544 if (inlined)
1545 *inlined = has_inline_data;
1546 if (has_inline_data || IS_ERR(ptr: ret))
1547 goto cleanup_and_exit;
1548 }
1549
1550 if ((namelen <= 2) && (name[0] == '.') &&
1551 (name[1] == '.' || name[1] == '\0')) {
1552 /*
1553 * "." or ".." will only be in the first block
1554 * NFS may look up ".."; "." should be handled by the VFS
1555 */
1556 block = start = 0;
1557 nblocks = 1;
1558 goto restart;
1559 }
1560 if (is_dx(dir)) {
1561 ret = ext4_dx_find_entry(dir, fname, res_dir);
1562 /*
1563 * On success, or if the error was file not found,
1564 * return. Otherwise, fall back to doing a search the
1565 * old fashioned way.
1566 */
1567 if (IS_ERR(ptr: ret) && PTR_ERR(ptr: ret) == ERR_BAD_DX_DIR)
1568 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1569 "falling back\n"));
1570 else if (!sb_no_casefold_compat_fallback(dir->i_sb) &&
1571 *res_dir == NULL && IS_CASEFOLDED(dir))
1572 dxtrace(printk(KERN_DEBUG "ext4_find_entry: casefold "
1573 "failed, falling back\n"));
1574 else
1575 goto cleanup_and_exit;
1576 ret = NULL;
1577 }
1578 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1579 if (!nblocks) {
1580 ret = NULL;
1581 goto cleanup_and_exit;
1582 }
1583 start = EXT4_I(dir)->i_dir_start_lookup;
1584 if (start >= nblocks)
1585 start = 0;
1586 block = start;
1587restart:
1588 do {
1589 /*
1590 * We deal with the read-ahead logic here.
1591 */
1592 cond_resched();
1593 if (ra_ptr >= ra_max) {
1594 /* Refill the readahead buffer */
1595 ra_ptr = 0;
1596 if (block < start)
1597 ra_max = start - block;
1598 else
1599 ra_max = nblocks - block;
1600 ra_max = min(ra_max, ARRAY_SIZE(bh_use));
1601 retval = ext4_bread_batch(inode: dir, block, bh_count: ra_max,
1602 wait: false /* wait */, bhs: bh_use);
1603 if (retval) {
1604 ret = ERR_PTR(error: retval);
1605 ra_max = 0;
1606 goto cleanup_and_exit;
1607 }
1608 }
1609 if ((bh = bh_use[ra_ptr++]) == NULL)
1610 goto next;
1611 wait_on_buffer(bh);
1612 if (!buffer_uptodate(bh)) {
1613 EXT4_ERROR_INODE_ERR(dir, EIO,
1614 "reading directory lblock %lu",
1615 (unsigned long) block);
1616 brelse(bh);
1617 ret = ERR_PTR(error: -EIO);
1618 goto cleanup_and_exit;
1619 }
1620 if (!buffer_verified(bh) &&
1621 !is_dx_internal_node(dir, block,
1622 de: (struct ext4_dir_entry *)bh->b_data) &&
1623 !ext4_dirblock_csum_verify(inode: dir, bh)) {
1624 EXT4_ERROR_INODE_ERR(dir, EFSBADCRC,
1625 "checksumming directory "
1626 "block %lu", (unsigned long)block);
1627 brelse(bh);
1628 ret = ERR_PTR(error: -EFSBADCRC);
1629 goto cleanup_and_exit;
1630 }
1631 set_buffer_verified(bh);
1632 i = search_dirblock(bh, dir, fname,
1633 offset: block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
1634 if (i == 1) {
1635 EXT4_I(dir)->i_dir_start_lookup = block;
1636 ret = bh;
1637 goto cleanup_and_exit;
1638 } else {
1639 brelse(bh);
1640 if (i < 0) {
1641 ret = ERR_PTR(error: i);
1642 goto cleanup_and_exit;
1643 }
1644 }
1645 next:
1646 if (++block >= nblocks)
1647 block = 0;
1648 } while (block != start);
1649
1650 /*
1651 * If the directory has grown while we were searching, then
1652 * search the last part of the directory before giving up.
1653 */
1654 block = nblocks;
1655 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1656 if (block < nblocks) {
1657 start = 0;
1658 goto restart;
1659 }
1660
1661cleanup_and_exit:
1662 /* Clean up the read-ahead blocks */
1663 for (; ra_ptr < ra_max; ra_ptr++)
1664 brelse(bh: bh_use[ra_ptr]);
1665 return ret;
1666}
1667
1668static struct buffer_head *ext4_find_entry(struct inode *dir,
1669 const struct qstr *d_name,
1670 struct ext4_dir_entry_2 **res_dir,
1671 int *inlined)
1672{
1673 int err;
1674 struct ext4_filename fname;
1675 struct buffer_head *bh;
1676
1677 err = ext4_fname_setup_filename(dir, iname: d_name, lookup: 1, fname: &fname);
1678 if (err == -ENOENT)
1679 return NULL;
1680 if (err)
1681 return ERR_PTR(error: err);
1682
1683 bh = __ext4_find_entry(dir, fname: &fname, res_dir, inlined);
1684
1685 ext4_fname_free_filename(fname: &fname);
1686 return bh;
1687}
1688
1689static struct buffer_head *ext4_lookup_entry(struct inode *dir,
1690 struct dentry *dentry,
1691 struct ext4_dir_entry_2 **res_dir)
1692{
1693 int err;
1694 struct ext4_filename fname;
1695 struct buffer_head *bh;
1696
1697 err = ext4_fname_prepare_lookup(dir, dentry, fname: &fname);
1698 if (err == -ENOENT)
1699 return NULL;
1700 if (err)
1701 return ERR_PTR(error: err);
1702
1703 bh = __ext4_find_entry(dir, fname: &fname, res_dir, NULL);
1704
1705 ext4_fname_free_filename(fname: &fname);
1706 return bh;
1707}
1708
1709static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
1710 struct ext4_filename *fname,
1711 struct ext4_dir_entry_2 **res_dir)
1712{
1713 struct super_block * sb = dir->i_sb;
1714 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1715 struct buffer_head *bh;
1716 ext4_lblk_t block;
1717 int retval;
1718
1719#ifdef CONFIG_FS_ENCRYPTION
1720 *res_dir = NULL;
1721#endif
1722 frame = dx_probe(fname, dir, NULL, frame_in: frames);
1723 if (IS_ERR(ptr: frame))
1724 return ERR_CAST(ptr: frame);
1725 do {
1726 block = dx_get_block(entry: frame->at);
1727 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
1728 if (IS_ERR(ptr: bh))
1729 goto errout;
1730
1731 retval = search_dirblock(bh, dir, fname,
1732 offset: block << EXT4_BLOCK_SIZE_BITS(sb),
1733 res_dir);
1734 if (retval == 1)
1735 goto success;
1736 brelse(bh);
1737 if (retval < 0) {
1738 bh = ERR_PTR(ERR_BAD_DX_DIR);
1739 goto errout;
1740 }
1741
1742 /* Check to see if we should continue to search */
1743 retval = ext4_htree_next_block(dir, hash: fname->hinfo.hash, frame,
1744 frames, NULL);
1745 if (retval < 0) {
1746 ext4_warning_inode(dir,
1747 "error %d reading directory index block",
1748 retval);
1749 bh = ERR_PTR(error: retval);
1750 goto errout;
1751 }
1752 } while (retval == 1);
1753
1754 bh = NULL;
1755errout:
1756 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name));
1757success:
1758 dx_release(frames);
1759 return bh;
1760}
1761
1762static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
1763{
1764 struct inode *inode;
1765 struct ext4_dir_entry_2 *de;
1766 struct buffer_head *bh;
1767
1768 if (dentry->d_name.len > EXT4_NAME_LEN)
1769 return ERR_PTR(error: -ENAMETOOLONG);
1770
1771 bh = ext4_lookup_entry(dir, dentry, res_dir: &de);
1772 if (IS_ERR(ptr: bh))
1773 return ERR_CAST(ptr: bh);
1774 inode = NULL;
1775 if (bh) {
1776 __u32 ino = le32_to_cpu(de->inode);
1777 brelse(bh);
1778 if (!ext4_valid_inum(sb: dir->i_sb, ino)) {
1779 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1780 return ERR_PTR(error: -EFSCORRUPTED);
1781 }
1782 if (unlikely(ino == dir->i_ino)) {
1783 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
1784 dentry);
1785 return ERR_PTR(error: -EFSCORRUPTED);
1786 }
1787 inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL);
1788 if (inode == ERR_PTR(error: -ESTALE)) {
1789 EXT4_ERROR_INODE(dir,
1790 "deleted inode referenced: %u",
1791 ino);
1792 return ERR_PTR(error: -EFSCORRUPTED);
1793 }
1794 if (!IS_ERR(ptr: inode) && IS_ENCRYPTED(dir) &&
1795 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
1796 !fscrypt_has_permitted_context(parent: dir, child: inode)) {
1797 ext4_warning(inode->i_sb,
1798 "Inconsistent encryption contexts: %lu/%lu",
1799 dir->i_ino, inode->i_ino);
1800 iput(inode);
1801 return ERR_PTR(error: -EPERM);
1802 }
1803 }
1804
1805 if (IS_ENABLED(CONFIG_UNICODE) && !inode && IS_CASEFOLDED(dir)) {
1806 /* Eventually we want to call d_add_ci(dentry, NULL)
1807 * for negative dentries in the encoding case as
1808 * well. For now, prevent the negative dentry
1809 * from being cached.
1810 */
1811 return NULL;
1812 }
1813
1814 return d_splice_alias(inode, dentry);
1815}
1816
1817
1818struct dentry *ext4_get_parent(struct dentry *child)
1819{
1820 __u32 ino;
1821 struct ext4_dir_entry_2 * de;
1822 struct buffer_head *bh;
1823
1824 bh = ext4_find_entry(dir: d_inode(dentry: child), d_name: &dotdot_name, res_dir: &de, NULL);
1825 if (IS_ERR(ptr: bh))
1826 return ERR_CAST(ptr: bh);
1827 if (!bh)
1828 return ERR_PTR(error: -ENOENT);
1829 ino = le32_to_cpu(de->inode);
1830 brelse(bh);
1831
1832 if (!ext4_valid_inum(sb: child->d_sb, ino)) {
1833 EXT4_ERROR_INODE(d_inode(child),
1834 "bad parent inode number: %u", ino);
1835 return ERR_PTR(error: -EFSCORRUPTED);
1836 }
1837
1838 return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL));
1839}
1840
1841/*
1842 * Move count entries from end of map between two memory locations.
1843 * Returns pointer to last entry moved.
1844 */
1845static struct ext4_dir_entry_2 *
1846dx_move_dirents(struct inode *dir, char *from, char *to,
1847 struct dx_map_entry *map, int count,
1848 unsigned blocksize)
1849{
1850 unsigned rec_len = 0;
1851
1852 while (count--) {
1853 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
1854 (from + (map->offs<<2));
1855 rec_len = ext4_dir_rec_len(name_len: de->name_len, dir);
1856
1857 memcpy (to, from: de, len: rec_len);
1858 ((struct ext4_dir_entry_2 *) to)->rec_len =
1859 ext4_rec_len_to_disk(len: rec_len, blocksize);
1860
1861 /* wipe dir_entry excluding the rec_len field */
1862 de->inode = 0;
1863 memset(s: &de->name_len, c: 0, n: ext4_rec_len_from_disk(dlen: de->rec_len,
1864 blocksize) -
1865 offsetof(struct ext4_dir_entry_2,
1866 name_len));
1867
1868 map++;
1869 to += rec_len;
1870 }
1871 return (struct ext4_dir_entry_2 *) (to - rec_len);
1872}
1873
1874/*
1875 * Compact each dir entry in the range to the minimal rec_len.
1876 * Returns pointer to last entry in range.
1877 */
1878static struct ext4_dir_entry_2 *dx_pack_dirents(struct inode *dir, char *base,
1879 unsigned int blocksize)
1880{
1881 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
1882 unsigned rec_len = 0;
1883
1884 prev = to = de;
1885 while ((char*)de < base + blocksize) {
1886 next = ext4_next_entry(p: de, blocksize);
1887 if (de->inode && de->name_len) {
1888 rec_len = ext4_dir_rec_len(name_len: de->name_len, dir);
1889 if (de > to)
1890 memmove(dest: to, src: de, count: rec_len);
1891 to->rec_len = ext4_rec_len_to_disk(len: rec_len, blocksize);
1892 prev = to;
1893 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
1894 }
1895 de = next;
1896 }
1897 return prev;
1898}
1899
1900/*
1901 * Split a full leaf block to make room for a new dir entry.
1902 * Allocate a new block, and move entries so that they are approx. equally full.
1903 * Returns pointer to de in block into which the new entry will be inserted.
1904 */
1905static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1906 struct buffer_head **bh,struct dx_frame *frame,
1907 struct dx_hash_info *hinfo)
1908{
1909 unsigned blocksize = dir->i_sb->s_blocksize;
1910 unsigned continued;
1911 int count;
1912 struct buffer_head *bh2;
1913 ext4_lblk_t newblock;
1914 u32 hash2;
1915 struct dx_map_entry *map;
1916 char *data1 = (*bh)->b_data, *data2;
1917 unsigned split, move, size;
1918 struct ext4_dir_entry_2 *de = NULL, *de2;
1919 int csum_size = 0;
1920 int err = 0, i;
1921
1922 if (ext4_has_feature_metadata_csum(sb: dir->i_sb))
1923 csum_size = sizeof(struct ext4_dir_entry_tail);
1924
1925 bh2 = ext4_append(handle, inode: dir, block: &newblock);
1926 if (IS_ERR(ptr: bh2)) {
1927 brelse(bh: *bh);
1928 *bh = NULL;
1929 return ERR_CAST(ptr: bh2);
1930 }
1931
1932 BUFFER_TRACE(*bh, "get_write_access");
1933 err = ext4_journal_get_write_access(handle, dir->i_sb, *bh,
1934 EXT4_JTR_NONE);
1935 if (err)
1936 goto journal_error;
1937
1938 BUFFER_TRACE(frame->bh, "get_write_access");
1939 err = ext4_journal_get_write_access(handle, dir->i_sb, frame->bh,
1940 EXT4_JTR_NONE);
1941 if (err)
1942 goto journal_error;
1943
1944 data2 = bh2->b_data;
1945
1946 /* create map in the end of data2 block */
1947 map = (struct dx_map_entry *) (data2 + blocksize);
1948 count = dx_make_map(dir, bh: *bh, hinfo, map_tail: map);
1949 if (count < 0) {
1950 err = count;
1951 goto journal_error;
1952 }
1953 map -= count;
1954 dx_sort_map(map, count);
1955 /* Ensure that neither split block is over half full */
1956 size = 0;
1957 move = 0;
1958 for (i = count-1; i >= 0; i--) {
1959 /* is more than half of this entry in 2nd half of the block? */
1960 if (size + map[i].size/2 > blocksize/2)
1961 break;
1962 size += map[i].size;
1963 move++;
1964 }
1965 /*
1966 * map index at which we will split
1967 *
1968 * If the sum of active entries didn't exceed half the block size, just
1969 * split it in half by count; each resulting block will have at least
1970 * half the space free.
1971 */
1972 if (i >= 0)
1973 split = count - move;
1974 else
1975 split = count/2;
1976
1977 if (WARN_ON_ONCE(split == 0)) {
1978 /* Should never happen, but avoid out-of-bounds access below */
1979 ext4_error_inode_block(dir, (*bh)->b_blocknr, 0,
1980 "bad indexed directory? hash=%08x:%08x count=%d move=%u",
1981 hinfo->hash, hinfo->minor_hash, count, move);
1982 err = -EFSCORRUPTED;
1983 goto out;
1984 }
1985
1986 hash2 = map[split].hash;
1987 continued = hash2 == map[split - 1].hash;
1988 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1989 (unsigned long)dx_get_block(frame->at),
1990 hash2, split, count-split));
1991
1992 /* Fancy dance to stay within two buffers */
1993 de2 = dx_move_dirents(dir, from: data1, to: data2, map: map + split, count: count - split,
1994 blocksize);
1995 de = dx_pack_dirents(dir, base: data1, blocksize);
1996 de->rec_len = ext4_rec_len_to_disk(len: data1 + (blocksize - csum_size) -
1997 (char *) de,
1998 blocksize);
1999 de2->rec_len = ext4_rec_len_to_disk(len: data2 + (blocksize - csum_size) -
2000 (char *) de2,
2001 blocksize);
2002 if (csum_size) {
2003 ext4_initialize_dirent_tail(bh: *bh, blocksize);
2004 ext4_initialize_dirent_tail(bh: bh2, blocksize);
2005 }
2006
2007 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
2008 blocksize, 1));
2009 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,
2010 blocksize, 1));
2011
2012 /* Which block gets the new entry? */
2013 if (hinfo->hash >= hash2) {
2014 swap(*bh, bh2);
2015 de = de2;
2016 }
2017 dx_insert_block(frame, hash: hash2 + continued, block: newblock);
2018 err = ext4_handle_dirty_dirblock(handle, inode: dir, bh: bh2);
2019 if (err)
2020 goto journal_error;
2021 err = ext4_handle_dirty_dx_node(handle, inode: dir, bh: frame->bh);
2022 if (err)
2023 goto journal_error;
2024 brelse(bh: bh2);
2025 dxtrace(dx_show_index("frame", frame->entries));
2026 return de;
2027
2028journal_error:
2029 ext4_std_error(dir->i_sb, err);
2030out:
2031 brelse(bh: *bh);
2032 brelse(bh: bh2);
2033 *bh = NULL;
2034 return ERR_PTR(error: err);
2035}
2036
2037int ext4_find_dest_de(struct inode *dir, struct buffer_head *bh,
2038 void *buf, int buf_size,
2039 struct ext4_filename *fname,
2040 struct ext4_dir_entry_2 **dest_de)
2041{
2042 struct ext4_dir_entry_2 *de;
2043 unsigned short reclen = ext4_dir_rec_len(fname_len(fname), dir);
2044 int nlen, rlen;
2045 unsigned int offset = 0;
2046 char *top;
2047
2048 de = buf;
2049 top = buf + buf_size - reclen;
2050 while ((char *) de <= top) {
2051 if (ext4_check_dir_entry(dir, NULL, de, bh,
2052 buf, buf_size, offset))
2053 return -EFSCORRUPTED;
2054 if (ext4_match(parent: dir, fname, de))
2055 return -EEXIST;
2056 nlen = ext4_dir_rec_len(name_len: de->name_len, dir);
2057 rlen = ext4_rec_len_from_disk(dlen: de->rec_len, blocksize: buf_size);
2058 if ((de->inode ? rlen - nlen : rlen) >= reclen)
2059 break;
2060 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
2061 offset += rlen;
2062 }
2063 if ((char *) de > top)
2064 return -ENOSPC;
2065
2066 *dest_de = de;
2067 return 0;
2068}
2069
2070void ext4_insert_dentry(struct inode *dir,
2071 struct inode *inode,
2072 struct ext4_dir_entry_2 *de,
2073 int buf_size,
2074 struct ext4_filename *fname)
2075{
2076
2077 int nlen, rlen;
2078
2079 nlen = ext4_dir_rec_len(name_len: de->name_len, dir);
2080 rlen = ext4_rec_len_from_disk(dlen: de->rec_len, blocksize: buf_size);
2081 if (de->inode) {
2082 struct ext4_dir_entry_2 *de1 =
2083 (struct ext4_dir_entry_2 *)((char *)de + nlen);
2084 de1->rec_len = ext4_rec_len_to_disk(len: rlen - nlen, blocksize: buf_size);
2085 de->rec_len = ext4_rec_len_to_disk(len: nlen, blocksize: buf_size);
2086 de = de1;
2087 }
2088 de->file_type = EXT4_FT_UNKNOWN;
2089 de->inode = cpu_to_le32(inode->i_ino);
2090 ext4_set_de_type(sb: inode->i_sb, de, mode: inode->i_mode);
2091 de->name_len = fname_len(fname);
2092 memcpy(to: de->name, fname_name(fname), fname_len(fname));
2093 if (ext4_hash_in_dirent(inode: dir)) {
2094 struct dx_hash_info *hinfo = &fname->hinfo;
2095
2096 EXT4_DIRENT_HASHES(de)->hash = cpu_to_le32(hinfo->hash);
2097 EXT4_DIRENT_HASHES(de)->minor_hash =
2098 cpu_to_le32(hinfo->minor_hash);
2099 }
2100}
2101
2102/*
2103 * Add a new entry into a directory (leaf) block. If de is non-NULL,
2104 * it points to a directory entry which is guaranteed to be large
2105 * enough for new directory entry. If de is NULL, then
2106 * add_dirent_to_buf will attempt search the directory block for
2107 * space. It will return -ENOSPC if no space is available, and -EIO
2108 * and -EEXIST if directory entry already exists.
2109 */
2110static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
2111 struct inode *dir,
2112 struct inode *inode, struct ext4_dir_entry_2 *de,
2113 struct buffer_head *bh)
2114{
2115 unsigned int blocksize = dir->i_sb->s_blocksize;
2116 int csum_size = 0;
2117 int err, err2;
2118
2119 if (ext4_has_feature_metadata_csum(sb: inode->i_sb))
2120 csum_size = sizeof(struct ext4_dir_entry_tail);
2121
2122 if (!de) {
2123 err = ext4_find_dest_de(dir, bh, buf: bh->b_data,
2124 buf_size: blocksize - csum_size, fname, dest_de: &de);
2125 if (err)
2126 return err;
2127 }
2128 BUFFER_TRACE(bh, "get_write_access");
2129 err = ext4_journal_get_write_access(handle, dir->i_sb, bh,
2130 EXT4_JTR_NONE);
2131 if (err) {
2132 ext4_std_error(dir->i_sb, err);
2133 return err;
2134 }
2135
2136 /* By now the buffer is marked for journaling */
2137 ext4_insert_dentry(dir, inode, de, buf_size: blocksize, fname);
2138
2139 /*
2140 * XXX shouldn't update any times until successful
2141 * completion of syscall, but too many callers depend
2142 * on this.
2143 *
2144 * XXX similarly, too many callers depend on
2145 * ext4_new_inode() setting the times, but error
2146 * recovery deletes the inode, so the worst that can
2147 * happen is that the times are slightly out of date
2148 * and/or different from the directory change time.
2149 */
2150 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
2151 ext4_update_dx_flag(inode: dir);
2152 inode_inc_iversion(inode: dir);
2153 err2 = ext4_mark_inode_dirty(handle, dir);
2154 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2155 err = ext4_handle_dirty_dirblock(handle, inode: dir, bh);
2156 if (err)
2157 ext4_std_error(dir->i_sb, err);
2158 return err ? err : err2;
2159}
2160
2161static bool ext4_check_dx_root(struct inode *dir, struct dx_root *root)
2162{
2163 struct fake_dirent *fde;
2164 const char *error_msg;
2165 unsigned int rlen;
2166 unsigned int blocksize = dir->i_sb->s_blocksize;
2167 char *blockend = (char *)root + dir->i_sb->s_blocksize;
2168
2169 fde = &root->dot;
2170 if (unlikely(fde->name_len != 1)) {
2171 error_msg = "invalid name_len for '.'";
2172 goto corrupted;
2173 }
2174 if (unlikely(strncmp(root->dot_name, ".", fde->name_len))) {
2175 error_msg = "invalid name for '.'";
2176 goto corrupted;
2177 }
2178 rlen = ext4_rec_len_from_disk(dlen: fde->rec_len, blocksize);
2179 if (unlikely((char *)fde + rlen >= blockend)) {
2180 error_msg = "invalid rec_len for '.'";
2181 goto corrupted;
2182 }
2183
2184 fde = &root->dotdot;
2185 if (unlikely(fde->name_len != 2)) {
2186 error_msg = "invalid name_len for '..'";
2187 goto corrupted;
2188 }
2189 if (unlikely(strncmp(root->dotdot_name, "..", fde->name_len))) {
2190 error_msg = "invalid name for '..'";
2191 goto corrupted;
2192 }
2193 rlen = ext4_rec_len_from_disk(dlen: fde->rec_len, blocksize);
2194 if (unlikely((char *)fde + rlen >= blockend)) {
2195 error_msg = "invalid rec_len for '..'";
2196 goto corrupted;
2197 }
2198
2199 return true;
2200
2201corrupted:
2202 EXT4_ERROR_INODE(dir, "Corrupt dir, %s, running e2fsck is recommended",
2203 error_msg);
2204 return false;
2205}
2206
2207/*
2208 * This converts a one block unindexed directory to a 3 block indexed
2209 * directory, and adds the dentry to the indexed directory.
2210 */
2211static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
2212 struct inode *dir,
2213 struct inode *inode, struct buffer_head *bh)
2214{
2215 struct buffer_head *bh2;
2216 struct dx_root *root;
2217 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2218 struct dx_entry *entries;
2219 struct ext4_dir_entry_2 *de, *de2;
2220 char *data2, *top;
2221 unsigned len;
2222 int retval;
2223 unsigned blocksize;
2224 ext4_lblk_t block;
2225 struct fake_dirent *fde;
2226 int csum_size = 0;
2227
2228 if (ext4_has_feature_metadata_csum(sb: inode->i_sb))
2229 csum_size = sizeof(struct ext4_dir_entry_tail);
2230
2231 blocksize = dir->i_sb->s_blocksize;
2232 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
2233 BUFFER_TRACE(bh, "get_write_access");
2234 retval = ext4_journal_get_write_access(handle, dir->i_sb, bh,
2235 EXT4_JTR_NONE);
2236 if (retval) {
2237 ext4_std_error(dir->i_sb, retval);
2238 brelse(bh);
2239 return retval;
2240 }
2241
2242 root = (struct dx_root *) bh->b_data;
2243 if (!ext4_check_dx_root(dir, root)) {
2244 brelse(bh);
2245 return -EFSCORRUPTED;
2246 }
2247
2248 /* The 0th block becomes the root, move the dirents out */
2249 fde = &root->dotdot;
2250 de = (struct ext4_dir_entry_2 *)((char *)fde +
2251 ext4_rec_len_from_disk(dlen: fde->rec_len, blocksize));
2252 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
2253
2254 /* Allocate new block for the 0th block's dirents */
2255 bh2 = ext4_append(handle, inode: dir, block: &block);
2256 if (IS_ERR(ptr: bh2)) {
2257 brelse(bh);
2258 return PTR_ERR(ptr: bh2);
2259 }
2260 ext4_set_inode_flag(inode: dir, bit: EXT4_INODE_INDEX);
2261 data2 = bh2->b_data;
2262
2263 memcpy(to: data2, from: de, len);
2264 memset(s: de, c: 0, n: len); /* wipe old data */
2265 de = (struct ext4_dir_entry_2 *) data2;
2266 top = data2 + len;
2267 while ((char *)(de2 = ext4_next_entry(p: de, blocksize)) < top) {
2268 if (ext4_check_dir_entry(dir, NULL, de, bh2, data2, len,
2269 (char *)de - data2)) {
2270 brelse(bh: bh2);
2271 brelse(bh);
2272 return -EFSCORRUPTED;
2273 }
2274 de = de2;
2275 }
2276 de->rec_len = ext4_rec_len_to_disk(len: data2 + (blocksize - csum_size) -
2277 (char *) de, blocksize);
2278
2279 if (csum_size)
2280 ext4_initialize_dirent_tail(bh: bh2, blocksize);
2281
2282 /* Initialize the root; the dot dirents already exist */
2283 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
2284 de->rec_len = ext4_rec_len_to_disk(
2285 len: blocksize - ext4_dir_rec_len(name_len: 2, NULL), blocksize);
2286 memset (s: &root->info, c: 0, n: sizeof(root->info));
2287 root->info.info_length = sizeof(root->info);
2288 if (ext4_hash_in_dirent(inode: dir))
2289 root->info.hash_version = DX_HASH_SIPHASH;
2290 else
2291 root->info.hash_version =
2292 EXT4_SB(sb: dir->i_sb)->s_def_hash_version;
2293
2294 entries = root->entries;
2295 dx_set_block(entry: entries, value: 1);
2296 dx_set_count(entries, value: 1);
2297 dx_set_limit(entries, value: dx_root_limit(dir, infosize: sizeof(root->info)));
2298
2299 /* Initialize as for dx_probe */
2300 fname->hinfo.hash_version = root->info.hash_version;
2301 if (fname->hinfo.hash_version <= DX_HASH_TEA)
2302 fname->hinfo.hash_version += EXT4_SB(sb: dir->i_sb)->s_hash_unsigned;
2303 fname->hinfo.seed = EXT4_SB(sb: dir->i_sb)->s_hash_seed;
2304
2305 /* casefolded encrypted hashes are computed on fname setup */
2306 if (!ext4_hash_in_dirent(inode: dir)) {
2307 int err = ext4fs_dirhash(dir, fname_name(fname),
2308 fname_len(fname), hinfo: &fname->hinfo);
2309 if (err < 0) {
2310 brelse(bh: bh2);
2311 brelse(bh);
2312 return err;
2313 }
2314 }
2315 memset(s: frames, c: 0, n: sizeof(frames));
2316 frame = frames;
2317 frame->entries = entries;
2318 frame->at = entries;
2319 frame->bh = bh;
2320
2321 retval = ext4_handle_dirty_dx_node(handle, inode: dir, bh: frame->bh);
2322 if (retval)
2323 goto out_frames;
2324 retval = ext4_handle_dirty_dirblock(handle, inode: dir, bh: bh2);
2325 if (retval)
2326 goto out_frames;
2327
2328 de = do_split(handle,dir, bh: &bh2, frame, hinfo: &fname->hinfo);
2329 if (IS_ERR(ptr: de)) {
2330 retval = PTR_ERR(ptr: de);
2331 goto out_frames;
2332 }
2333
2334 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh: bh2);
2335out_frames:
2336 /*
2337 * Even if the block split failed, we have to properly write
2338 * out all the changes we did so far. Otherwise we can end up
2339 * with corrupted filesystem.
2340 */
2341 if (retval)
2342 ext4_mark_inode_dirty(handle, dir);
2343 dx_release(frames);
2344 brelse(bh: bh2);
2345 return retval;
2346}
2347
2348/*
2349 * ext4_add_entry()
2350 *
2351 * adds a file entry to the specified directory, using the same
2352 * semantics as ext4_find_entry(). It returns NULL if it failed.
2353 *
2354 * NOTE!! The inode part of 'de' is left at 0 - which means you
2355 * may not sleep between calling this and putting something into
2356 * the entry, as someone else might have used it while you slept.
2357 */
2358static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
2359 struct inode *inode)
2360{
2361 struct inode *dir = d_inode(dentry: dentry->d_parent);
2362 struct buffer_head *bh = NULL;
2363 struct ext4_dir_entry_2 *de;
2364 struct super_block *sb;
2365 struct ext4_filename fname;
2366 int retval;
2367 int dx_fallback=0;
2368 unsigned blocksize;
2369 ext4_lblk_t block, blocks;
2370 int csum_size = 0;
2371
2372 if (ext4_has_feature_metadata_csum(sb: inode->i_sb))
2373 csum_size = sizeof(struct ext4_dir_entry_tail);
2374
2375 sb = dir->i_sb;
2376 blocksize = sb->s_blocksize;
2377
2378 if (fscrypt_is_nokey_name(dentry))
2379 return -ENOKEY;
2380
2381 if (!generic_ci_validate_strict_name(dir, name: &dentry->d_name))
2382 return -EINVAL;
2383
2384 retval = ext4_fname_setup_filename(dir, iname: &dentry->d_name, lookup: 0, fname: &fname);
2385 if (retval)
2386 return retval;
2387
2388 if (ext4_has_inline_data(inode: dir)) {
2389 retval = ext4_try_add_inline_entry(handle, fname: &fname, dir, inode);
2390 if (retval < 0)
2391 goto out;
2392 if (retval == 1) {
2393 retval = 0;
2394 goto out;
2395 }
2396 }
2397
2398 if (is_dx(dir)) {
2399 retval = ext4_dx_add_entry(handle, fname: &fname, dir, inode);
2400 if (!retval || (retval != ERR_BAD_DX_DIR))
2401 goto out;
2402 /* Can we just ignore htree data? */
2403 if (ext4_has_feature_metadata_csum(sb)) {
2404 EXT4_ERROR_INODE(dir,
2405 "Directory has corrupted htree index.");
2406 retval = -EFSCORRUPTED;
2407 goto out;
2408 }
2409 ext4_clear_inode_flag(inode: dir, bit: EXT4_INODE_INDEX);
2410 dx_fallback++;
2411 retval = ext4_mark_inode_dirty(handle, dir);
2412 if (unlikely(retval))
2413 goto out;
2414 }
2415 blocks = dir->i_size >> sb->s_blocksize_bits;
2416 for (block = 0; block < blocks; block++) {
2417 bh = ext4_read_dirblock(dir, block, DIRENT);
2418 if (bh == NULL) {
2419 bh = ext4_bread(handle, dir, block,
2420 EXT4_GET_BLOCKS_CREATE);
2421 goto add_to_new_block;
2422 }
2423 if (IS_ERR(ptr: bh)) {
2424 retval = PTR_ERR(ptr: bh);
2425 bh = NULL;
2426 goto out;
2427 }
2428 retval = add_dirent_to_buf(handle, fname: &fname, dir, inode,
2429 NULL, bh);
2430 if (retval != -ENOSPC)
2431 goto out;
2432
2433 if (blocks == 1 && !dx_fallback &&
2434 ext4_has_feature_dir_index(sb)) {
2435 retval = make_indexed_dir(handle, fname: &fname, dir,
2436 inode, bh);
2437 bh = NULL; /* make_indexed_dir releases bh */
2438 goto out;
2439 }
2440 brelse(bh);
2441 }
2442 bh = ext4_append(handle, inode: dir, block: &block);
2443add_to_new_block:
2444 if (IS_ERR(ptr: bh)) {
2445 retval = PTR_ERR(ptr: bh);
2446 bh = NULL;
2447 goto out;
2448 }
2449 de = (struct ext4_dir_entry_2 *) bh->b_data;
2450 de->inode = 0;
2451 de->rec_len = ext4_rec_len_to_disk(len: blocksize - csum_size, blocksize);
2452
2453 if (csum_size)
2454 ext4_initialize_dirent_tail(bh, blocksize);
2455
2456 retval = add_dirent_to_buf(handle, fname: &fname, dir, inode, de, bh);
2457out:
2458 ext4_fname_free_filename(fname: &fname);
2459 brelse(bh);
2460 if (retval == 0)
2461 ext4_set_inode_state(inode, bit: EXT4_STATE_NEWENTRY);
2462 return retval;
2463}
2464
2465/*
2466 * Returns 0 for success, or a negative error value
2467 */
2468static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
2469 struct inode *dir, struct inode *inode)
2470{
2471 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2472 struct dx_entry *entries, *at;
2473 struct buffer_head *bh;
2474 struct super_block *sb = dir->i_sb;
2475 struct ext4_dir_entry_2 *de;
2476 int restart;
2477 int err;
2478
2479again:
2480 restart = 0;
2481 frame = dx_probe(fname, dir, NULL, frame_in: frames);
2482 if (IS_ERR(ptr: frame))
2483 return PTR_ERR(ptr: frame);
2484 entries = frame->entries;
2485 at = frame->at;
2486 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT_HTREE);
2487 if (IS_ERR(ptr: bh)) {
2488 err = PTR_ERR(ptr: bh);
2489 bh = NULL;
2490 goto cleanup;
2491 }
2492
2493 BUFFER_TRACE(bh, "get_write_access");
2494 err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
2495 if (err)
2496 goto journal_error;
2497
2498 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh);
2499 if (err != -ENOSPC)
2500 goto cleanup;
2501
2502 err = 0;
2503 /* Block full, should compress but for now just split */
2504 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
2505 dx_get_count(entries), dx_get_limit(entries)));
2506 /* Need to split index? */
2507 if (dx_get_count(entries) == dx_get_limit(entries)) {
2508 ext4_lblk_t newblock;
2509 int levels = frame - frames + 1;
2510 unsigned int icount;
2511 int add_level = 1;
2512 struct dx_entry *entries2;
2513 struct dx_node *node2;
2514 struct buffer_head *bh2;
2515
2516 while (frame > frames) {
2517 if (dx_get_count(entries: (frame - 1)->entries) <
2518 dx_get_limit(entries: (frame - 1)->entries)) {
2519 add_level = 0;
2520 break;
2521 }
2522 frame--; /* split higher index block */
2523 at = frame->at;
2524 entries = frame->entries;
2525 restart = 1;
2526 }
2527 if (add_level && levels == ext4_dir_htree_level(sb)) {
2528 ext4_warning(sb, "Directory (ino: %lu) index full, "
2529 "reach max htree level :%d",
2530 dir->i_ino, levels);
2531 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) {
2532 ext4_warning(sb, "Large directory feature is "
2533 "not enabled on this "
2534 "filesystem");
2535 }
2536 err = -ENOSPC;
2537 goto cleanup;
2538 }
2539 icount = dx_get_count(entries);
2540 bh2 = ext4_append(handle, inode: dir, block: &newblock);
2541 if (IS_ERR(ptr: bh2)) {
2542 err = PTR_ERR(ptr: bh2);
2543 goto cleanup;
2544 }
2545 node2 = (struct dx_node *)(bh2->b_data);
2546 entries2 = node2->entries;
2547 memset(s: &node2->fake, c: 0, n: sizeof(struct fake_dirent));
2548 node2->fake.rec_len = ext4_rec_len_to_disk(len: sb->s_blocksize,
2549 blocksize: sb->s_blocksize);
2550 BUFFER_TRACE(frame->bh, "get_write_access");
2551 err = ext4_journal_get_write_access(handle, sb, frame->bh,
2552 EXT4_JTR_NONE);
2553 if (err) {
2554 brelse(bh: bh2);
2555 goto journal_error;
2556 }
2557 if (!add_level) {
2558 unsigned icount1 = icount/2, icount2 = icount - icount1;
2559 unsigned hash2 = dx_get_hash(entry: entries + icount1);
2560 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2561 icount1, icount2));
2562
2563 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
2564 err = ext4_journal_get_write_access(handle, sb,
2565 (frame - 1)->bh,
2566 EXT4_JTR_NONE);
2567 if (err) {
2568 brelse(bh: bh2);
2569 goto journal_error;
2570 }
2571
2572 memcpy(to: (char *) entries2, from: (char *) (entries + icount1),
2573 len: icount2 * sizeof(struct dx_entry));
2574 dx_set_count(entries, value: icount1);
2575 dx_set_count(entries: entries2, value: icount2);
2576 dx_set_limit(entries: entries2, value: dx_node_limit(dir));
2577
2578 /* Which index block gets the new entry? */
2579 if (at - entries >= icount1) {
2580 frame->at = at - entries - icount1 + entries2;
2581 frame->entries = entries = entries2;
2582 swap(frame->bh, bh2);
2583 }
2584 dx_insert_block(frame: (frame - 1), hash: hash2, block: newblock);
2585 dxtrace(dx_show_index("node", frame->entries));
2586 dxtrace(dx_show_index("node",
2587 ((struct dx_node *) bh2->b_data)->entries));
2588 err = ext4_handle_dirty_dx_node(handle, inode: dir, bh: bh2);
2589 if (err) {
2590 brelse(bh: bh2);
2591 goto journal_error;
2592 }
2593 brelse (bh: bh2);
2594 err = ext4_handle_dirty_dx_node(handle, inode: dir,
2595 bh: (frame - 1)->bh);
2596 if (err)
2597 goto journal_error;
2598 err = ext4_handle_dirty_dx_node(handle, inode: dir,
2599 bh: frame->bh);
2600 if (restart || err)
2601 goto journal_error;
2602 } else {
2603 struct dx_root *dxroot;
2604 memcpy(to: (char *) entries2, from: (char *) entries,
2605 len: icount * sizeof(struct dx_entry));
2606 dx_set_limit(entries: entries2, value: dx_node_limit(dir));
2607
2608 /* Set up root */
2609 dx_set_count(entries, value: 1);
2610 dx_set_block(entry: entries + 0, value: newblock);
2611 dxroot = (struct dx_root *)frames[0].bh->b_data;
2612 dxroot->info.indirect_levels += 1;
2613 dxtrace(printk(KERN_DEBUG
2614 "Creating %d level index...\n",
2615 dxroot->info.indirect_levels));
2616 err = ext4_handle_dirty_dx_node(handle, inode: dir, bh: frame->bh);
2617 if (err) {
2618 brelse(bh: bh2);
2619 goto journal_error;
2620 }
2621 err = ext4_handle_dirty_dx_node(handle, inode: dir, bh: bh2);
2622 brelse(bh: bh2);
2623 restart = 1;
2624 goto journal_error;
2625 }
2626 }
2627 de = do_split(handle, dir, bh: &bh, frame, hinfo: &fname->hinfo);
2628 if (IS_ERR(ptr: de)) {
2629 err = PTR_ERR(ptr: de);
2630 goto cleanup;
2631 }
2632 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh);
2633 goto cleanup;
2634
2635journal_error:
2636 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */
2637cleanup:
2638 brelse(bh);
2639 dx_release(frames);
2640 /* @restart is true means htree-path has been changed, we need to
2641 * repeat dx_probe() to find out valid htree-path
2642 */
2643 if (restart && err == 0)
2644 goto again;
2645 return err;
2646}
2647
2648/*
2649 * ext4_generic_delete_entry deletes a directory entry by merging it
2650 * with the previous entry
2651 */
2652int ext4_generic_delete_entry(struct inode *dir,
2653 struct ext4_dir_entry_2 *de_del,
2654 struct buffer_head *bh,
2655 void *entry_buf,
2656 int buf_size,
2657 int csum_size)
2658{
2659 struct ext4_dir_entry_2 *de, *pde;
2660 unsigned int blocksize = dir->i_sb->s_blocksize;
2661 int i;
2662
2663 i = 0;
2664 pde = NULL;
2665 de = entry_buf;
2666 while (i < buf_size - csum_size) {
2667 if (ext4_check_dir_entry(dir, NULL, de, bh,
2668 entry_buf, buf_size, i))
2669 return -EFSCORRUPTED;
2670 if (de == de_del) {
2671 if (pde) {
2672 pde->rec_len = ext4_rec_len_to_disk(
2673 len: ext4_rec_len_from_disk(dlen: pde->rec_len,
2674 blocksize) +
2675 ext4_rec_len_from_disk(dlen: de->rec_len,
2676 blocksize),
2677 blocksize);
2678
2679 /* wipe entire dir_entry */
2680 memset(s: de, c: 0, n: ext4_rec_len_from_disk(dlen: de->rec_len,
2681 blocksize));
2682 } else {
2683 /* wipe dir_entry excluding the rec_len field */
2684 de->inode = 0;
2685 memset(s: &de->name_len, c: 0,
2686 n: ext4_rec_len_from_disk(dlen: de->rec_len,
2687 blocksize) -
2688 offsetof(struct ext4_dir_entry_2,
2689 name_len));
2690 }
2691
2692 inode_inc_iversion(inode: dir);
2693 return 0;
2694 }
2695 i += ext4_rec_len_from_disk(dlen: de->rec_len, blocksize);
2696 pde = de;
2697 de = ext4_next_entry(p: de, blocksize);
2698 }
2699 return -ENOENT;
2700}
2701
2702static int ext4_delete_entry(handle_t *handle,
2703 struct inode *dir,
2704 struct ext4_dir_entry_2 *de_del,
2705 struct buffer_head *bh)
2706{
2707 int err, csum_size = 0;
2708
2709 if (ext4_has_inline_data(inode: dir)) {
2710 int has_inline_data = 1;
2711 err = ext4_delete_inline_entry(handle, dir, de_del, bh,
2712 has_inline_data: &has_inline_data);
2713 if (has_inline_data)
2714 return err;
2715 }
2716
2717 if (ext4_has_feature_metadata_csum(sb: dir->i_sb))
2718 csum_size = sizeof(struct ext4_dir_entry_tail);
2719
2720 BUFFER_TRACE(bh, "get_write_access");
2721 err = ext4_journal_get_write_access(handle, dir->i_sb, bh,
2722 EXT4_JTR_NONE);
2723 if (unlikely(err))
2724 goto out;
2725
2726 err = ext4_generic_delete_entry(dir, de_del, bh, entry_buf: bh->b_data,
2727 buf_size: dir->i_sb->s_blocksize, csum_size);
2728 if (err)
2729 goto out;
2730
2731 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2732 err = ext4_handle_dirty_dirblock(handle, inode: dir, bh);
2733 if (unlikely(err))
2734 goto out;
2735
2736 return 0;
2737out:
2738 if (err != -ENOENT)
2739 ext4_std_error(dir->i_sb, err);
2740 return err;
2741}
2742
2743/*
2744 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2
2745 * since this indicates that nlinks count was previously 1 to avoid overflowing
2746 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean
2747 * that subdirectory link counts are not being maintained accurately.
2748 *
2749 * The caller has already checked for i_nlink overflow in case the DIR_LINK
2750 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy
2751 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set
2752 * on regular files) and to avoid creating huge/slow non-HTREE directories.
2753 */
2754static void ext4_inc_count(struct inode *inode)
2755{
2756 inc_nlink(inode);
2757 if (is_dx(inode) &&
2758 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))
2759 set_nlink(inode, nlink: 1);
2760}
2761
2762/*
2763 * If a directory had nlink == 1, then we should let it be 1. This indicates
2764 * directory has >EXT4_LINK_MAX subdirs.
2765 */
2766static void ext4_dec_count(struct inode *inode)
2767{
2768 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2769 drop_nlink(inode);
2770}
2771
2772
2773/*
2774 * Add non-directory inode to a directory. On success, the inode reference is
2775 * consumed by dentry is instantiation. This is also indicated by clearing of
2776 * *inodep pointer. On failure, the caller is responsible for dropping the
2777 * inode reference in the safe context.
2778 */
2779static int ext4_add_nondir(handle_t *handle,
2780 struct dentry *dentry, struct inode **inodep)
2781{
2782 struct inode *dir = d_inode(dentry: dentry->d_parent);
2783 struct inode *inode = *inodep;
2784 int err = ext4_add_entry(handle, dentry, inode);
2785 if (!err) {
2786 err = ext4_mark_inode_dirty(handle, inode);
2787 if (IS_DIRSYNC(dir))
2788 ext4_handle_sync(handle);
2789 d_instantiate_new(dentry, inode);
2790 *inodep = NULL;
2791 return err;
2792 }
2793 drop_nlink(inode);
2794 ext4_mark_inode_dirty(handle, inode);
2795 ext4_orphan_add(handle, inode);
2796 unlock_new_inode(inode);
2797 return err;
2798}
2799
2800/*
2801 * By the time this is called, we already have created
2802 * the directory cache entry for the new file, but it
2803 * is so far negative - it has no inode.
2804 *
2805 * If the create succeeds, we fill in the inode information
2806 * with d_instantiate().
2807 */
2808static int ext4_create(struct mnt_idmap *idmap, struct inode *dir,
2809 struct dentry *dentry, umode_t mode, bool excl)
2810{
2811 handle_t *handle;
2812 struct inode *inode;
2813 int err, credits, retries = 0;
2814
2815 err = dquot_initialize(inode: dir);
2816 if (err)
2817 return err;
2818
2819 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2820 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2821retry:
2822 inode = ext4_new_inode_start_handle(idmap, dir, mode, &dentry->d_name,
2823 0, NULL, EXT4_HT_DIR, credits);
2824 handle = ext4_journal_current_handle();
2825 err = PTR_ERR(ptr: inode);
2826 if (!IS_ERR(ptr: inode)) {
2827 inode->i_op = &ext4_file_inode_operations;
2828 inode->i_fop = &ext4_file_operations;
2829 ext4_set_aops(inode);
2830 err = ext4_add_nondir(handle, dentry, inodep: &inode);
2831 if (!err)
2832 ext4_fc_track_create(handle, dentry);
2833 }
2834 if (handle)
2835 ext4_journal_stop(handle);
2836 if (!IS_ERR_OR_NULL(ptr: inode))
2837 iput(inode);
2838 if (err == -ENOSPC && ext4_should_retry_alloc(sb: dir->i_sb, retries: &retries))
2839 goto retry;
2840 return err;
2841}
2842
2843static int ext4_mknod(struct mnt_idmap *idmap, struct inode *dir,
2844 struct dentry *dentry, umode_t mode, dev_t rdev)
2845{
2846 handle_t *handle;
2847 struct inode *inode;
2848 int err, credits, retries = 0;
2849
2850 err = dquot_initialize(inode: dir);
2851 if (err)
2852 return err;
2853
2854 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2855 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2856retry:
2857 inode = ext4_new_inode_start_handle(idmap, dir, mode, &dentry->d_name,
2858 0, NULL, EXT4_HT_DIR, credits);
2859 handle = ext4_journal_current_handle();
2860 err = PTR_ERR(ptr: inode);
2861 if (!IS_ERR(ptr: inode)) {
2862 init_special_inode(inode, inode->i_mode, rdev);
2863 inode->i_op = &ext4_special_inode_operations;
2864 err = ext4_add_nondir(handle, dentry, inodep: &inode);
2865 if (!err)
2866 ext4_fc_track_create(handle, dentry);
2867 }
2868 if (handle)
2869 ext4_journal_stop(handle);
2870 if (!IS_ERR_OR_NULL(ptr: inode))
2871 iput(inode);
2872 if (err == -ENOSPC && ext4_should_retry_alloc(sb: dir->i_sb, retries: &retries))
2873 goto retry;
2874 return err;
2875}
2876
2877static int ext4_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
2878 struct file *file, umode_t mode)
2879{
2880 handle_t *handle;
2881 struct inode *inode;
2882 int err, retries = 0;
2883
2884 err = dquot_initialize(inode: dir);
2885 if (err)
2886 return err;
2887
2888retry:
2889 inode = ext4_new_inode_start_handle(idmap, dir, mode,
2890 NULL, 0, NULL,
2891 EXT4_HT_DIR,
2892 EXT4_MAXQUOTAS_TRANS_BLOCKS(dir->i_sb) +
2893 4 + EXT4_XATTR_TRANS_BLOCKS);
2894 handle = ext4_journal_current_handle();
2895 err = PTR_ERR(ptr: inode);
2896 if (!IS_ERR(ptr: inode)) {
2897 inode->i_op = &ext4_file_inode_operations;
2898 inode->i_fop = &ext4_file_operations;
2899 ext4_set_aops(inode);
2900 d_tmpfile(file, inode);
2901 err = ext4_orphan_add(handle, inode);
2902 if (err)
2903 goto err_unlock_inode;
2904 mark_inode_dirty(inode);
2905 unlock_new_inode(inode);
2906 }
2907 if (handle)
2908 ext4_journal_stop(handle);
2909 if (err == -ENOSPC && ext4_should_retry_alloc(sb: dir->i_sb, retries: &retries))
2910 goto retry;
2911 return finish_open_simple(file, error: err);
2912err_unlock_inode:
2913 ext4_journal_stop(handle);
2914 unlock_new_inode(inode);
2915 return err;
2916}
2917
2918int ext4_init_dirblock(handle_t *handle, struct inode *inode,
2919 struct buffer_head *bh, unsigned int parent_ino,
2920 void *inline_buf, int inline_size)
2921{
2922 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) bh->b_data;
2923 size_t blocksize = bh->b_size;
2924 int csum_size = 0, header_size;
2925
2926 if (ext4_has_feature_metadata_csum(sb: inode->i_sb))
2927 csum_size = sizeof(struct ext4_dir_entry_tail);
2928
2929 de->inode = cpu_to_le32(inode->i_ino);
2930 de->name_len = 1;
2931 de->rec_len = ext4_rec_len_to_disk(len: ext4_dir_rec_len(name_len: de->name_len, NULL),
2932 blocksize);
2933 memcpy(to: de->name, from: ".", len: 2);
2934 ext4_set_de_type(sb: inode->i_sb, de, S_IFDIR);
2935
2936 de = ext4_next_entry(p: de, blocksize);
2937 de->inode = cpu_to_le32(parent_ino);
2938 de->name_len = 2;
2939 memcpy(to: de->name, from: "..", len: 3);
2940 ext4_set_de_type(sb: inode->i_sb, de, S_IFDIR);
2941 if (inline_buf) {
2942 de->rec_len = ext4_rec_len_to_disk(
2943 len: ext4_dir_rec_len(name_len: de->name_len, NULL),
2944 blocksize);
2945 de = ext4_next_entry(p: de, blocksize);
2946 header_size = (char *)de - bh->b_data;
2947 memcpy(to: (void *)de, from: inline_buf, len: inline_size);
2948 ext4_update_final_de(de_buf: bh->b_data, old_size: inline_size + header_size,
2949 new_size: blocksize - csum_size);
2950 } else {
2951 de->rec_len = ext4_rec_len_to_disk(len: blocksize -
2952 (csum_size + ext4_dir_rec_len(name_len: 1, NULL)),
2953 blocksize);
2954 }
2955
2956 if (csum_size)
2957 ext4_initialize_dirent_tail(bh, blocksize);
2958 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2959 set_buffer_uptodate(bh);
2960 set_buffer_verified(bh);
2961 return ext4_handle_dirty_dirblock(handle, inode, bh);
2962}
2963
2964int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2965 struct inode *inode)
2966{
2967 struct buffer_head *dir_block = NULL;
2968 ext4_lblk_t block = 0;
2969 int err;
2970
2971 if (ext4_test_inode_state(inode, bit: EXT4_STATE_MAY_INLINE_DATA)) {
2972 err = ext4_try_create_inline_dir(handle, parent: dir, inode);
2973 if (err < 0 && err != -ENOSPC)
2974 goto out;
2975 if (!err)
2976 goto out;
2977 }
2978
2979 set_nlink(inode, nlink: 2);
2980 inode->i_size = 0;
2981 dir_block = ext4_append(handle, inode, block: &block);
2982 if (IS_ERR(ptr: dir_block))
2983 return PTR_ERR(ptr: dir_block);
2984 err = ext4_init_dirblock(handle, inode, bh: dir_block, parent_ino: dir->i_ino, NULL, inline_size: 0);
2985out:
2986 brelse(bh: dir_block);
2987 return err;
2988}
2989
2990static struct dentry *ext4_mkdir(struct mnt_idmap *idmap, struct inode *dir,
2991 struct dentry *dentry, umode_t mode)
2992{
2993 handle_t *handle;
2994 struct inode *inode;
2995 int err, err2 = 0, credits, retries = 0;
2996
2997 if (EXT4_DIR_LINK_MAX(dir))
2998 return ERR_PTR(error: -EMLINK);
2999
3000 err = dquot_initialize(inode: dir);
3001 if (err)
3002 return ERR_PTR(error: err);
3003
3004 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3005 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
3006retry:
3007 inode = ext4_new_inode_start_handle(idmap, dir, S_IFDIR | mode,
3008 &dentry->d_name,
3009 0, NULL, EXT4_HT_DIR, credits);
3010 handle = ext4_journal_current_handle();
3011 err = PTR_ERR(ptr: inode);
3012 if (IS_ERR(ptr: inode))
3013 goto out_stop;
3014
3015 inode->i_op = &ext4_dir_inode_operations;
3016 inode->i_fop = &ext4_dir_operations;
3017 err = ext4_init_new_dir(handle, dir, inode);
3018 if (err)
3019 goto out_clear_inode;
3020 err = ext4_mark_inode_dirty(handle, inode);
3021 if (!err)
3022 err = ext4_add_entry(handle, dentry, inode);
3023 if (err) {
3024out_clear_inode:
3025 clear_nlink(inode);
3026 ext4_orphan_add(handle, inode);
3027 unlock_new_inode(inode);
3028 err2 = ext4_mark_inode_dirty(handle, inode);
3029 if (unlikely(err2))
3030 err = err2;
3031 ext4_journal_stop(handle);
3032 iput(inode);
3033 goto out_retry;
3034 }
3035 ext4_inc_count(inode: dir);
3036
3037 ext4_update_dx_flag(inode: dir);
3038 err = ext4_mark_inode_dirty(handle, dir);
3039 if (err)
3040 goto out_clear_inode;
3041 d_instantiate_new(dentry, inode);
3042 ext4_fc_track_create(handle, dentry);
3043 if (IS_DIRSYNC(dir))
3044 ext4_handle_sync(handle);
3045
3046out_stop:
3047 if (handle)
3048 ext4_journal_stop(handle);
3049out_retry:
3050 if (err == -ENOSPC && ext4_should_retry_alloc(sb: dir->i_sb, retries: &retries))
3051 goto retry;
3052 return ERR_PTR(error: err);
3053}
3054
3055/*
3056 * routine to check that the specified directory is empty (for rmdir)
3057 */
3058bool ext4_empty_dir(struct inode *inode)
3059{
3060 unsigned int offset;
3061 struct buffer_head *bh;
3062 struct ext4_dir_entry_2 *de;
3063 struct super_block *sb;
3064
3065 if (ext4_has_inline_data(inode)) {
3066 int has_inline_data = 1;
3067 int ret;
3068
3069 ret = empty_inline_dir(dir: inode, has_inline_data: &has_inline_data);
3070 if (has_inline_data)
3071 return ret;
3072 }
3073
3074 sb = inode->i_sb;
3075 if (inode->i_size < ext4_dir_rec_len(name_len: 1, NULL) +
3076 ext4_dir_rec_len(name_len: 2, NULL)) {
3077 EXT4_ERROR_INODE(inode, "invalid size");
3078 return false;
3079 }
3080 bh = ext4_read_dirblock(inode, 0, EITHER);
3081 if (IS_ERR(ptr: bh))
3082 return false;
3083
3084 de = (struct ext4_dir_entry_2 *) bh->b_data;
3085 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
3086 0) ||
3087 le32_to_cpu(de->inode) != inode->i_ino || de->name_len != 1 ||
3088 de->name[0] != '.') {
3089 ext4_warning_inode(inode, "directory missing '.'");
3090 brelse(bh);
3091 return false;
3092 }
3093 offset = ext4_rec_len_from_disk(dlen: de->rec_len, blocksize: sb->s_blocksize);
3094 de = ext4_next_entry(p: de, blocksize: sb->s_blocksize);
3095 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
3096 offset) ||
3097 le32_to_cpu(de->inode) == 0 || de->name_len != 2 ||
3098 de->name[0] != '.' || de->name[1] != '.') {
3099 ext4_warning_inode(inode, "directory missing '..'");
3100 brelse(bh);
3101 return false;
3102 }
3103 offset += ext4_rec_len_from_disk(dlen: de->rec_len, blocksize: sb->s_blocksize);
3104 while (offset < inode->i_size) {
3105 if (!(offset & (sb->s_blocksize - 1))) {
3106 unsigned int lblock;
3107 brelse(bh);
3108 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
3109 bh = ext4_read_dirblock(inode, lblock, EITHER);
3110 if (bh == NULL) {
3111 offset += sb->s_blocksize;
3112 continue;
3113 }
3114 if (IS_ERR(ptr: bh))
3115 return false;
3116 }
3117 de = (struct ext4_dir_entry_2 *) (bh->b_data +
3118 (offset & (sb->s_blocksize - 1)));
3119 if (ext4_check_dir_entry(inode, NULL, de, bh,
3120 bh->b_data, bh->b_size, offset) ||
3121 le32_to_cpu(de->inode)) {
3122 brelse(bh);
3123 return false;
3124 }
3125 offset += ext4_rec_len_from_disk(dlen: de->rec_len, blocksize: sb->s_blocksize);
3126 }
3127 brelse(bh);
3128 return true;
3129}
3130
3131static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
3132{
3133 int retval;
3134 struct inode *inode;
3135 struct buffer_head *bh;
3136 struct ext4_dir_entry_2 *de;
3137 handle_t *handle = NULL;
3138
3139 retval = ext4_emergency_state(sb: dir->i_sb);
3140 if (unlikely(retval))
3141 return retval;
3142
3143 /* Initialize quotas before so that eventual writes go in
3144 * separate transaction */
3145 retval = dquot_initialize(inode: dir);
3146 if (retval)
3147 return retval;
3148 retval = dquot_initialize(inode: d_inode(dentry));
3149 if (retval)
3150 return retval;
3151
3152 retval = -ENOENT;
3153 bh = ext4_find_entry(dir, d_name: &dentry->d_name, res_dir: &de, NULL);
3154 if (IS_ERR(ptr: bh))
3155 return PTR_ERR(ptr: bh);
3156 if (!bh)
3157 goto end_rmdir;
3158
3159 inode = d_inode(dentry);
3160
3161 retval = -EFSCORRUPTED;
3162 if (le32_to_cpu(de->inode) != inode->i_ino)
3163 goto end_rmdir;
3164
3165 retval = -ENOTEMPTY;
3166 if (!ext4_empty_dir(inode))
3167 goto end_rmdir;
3168
3169 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3170 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3171 if (IS_ERR(ptr: handle)) {
3172 retval = PTR_ERR(ptr: handle);
3173 handle = NULL;
3174 goto end_rmdir;
3175 }
3176
3177 if (IS_DIRSYNC(dir))
3178 ext4_handle_sync(handle);
3179
3180 retval = ext4_delete_entry(handle, dir, de_del: de, bh);
3181 if (retval)
3182 goto end_rmdir;
3183 if (!EXT4_DIR_LINK_EMPTY(inode))
3184 ext4_warning_inode(inode,
3185 "empty directory '%.*s' has too many links (%u)",
3186 dentry->d_name.len, dentry->d_name.name,
3187 inode->i_nlink);
3188 inode_inc_iversion(inode);
3189 clear_nlink(inode);
3190 /* There's no need to set i_disksize: the fact that i_nlink is
3191 * zero will ensure that the right thing happens during any
3192 * recovery. */
3193 inode->i_size = 0;
3194 ext4_orphan_add(handle, inode);
3195 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
3196 inode_set_ctime_current(inode);
3197 retval = ext4_mark_inode_dirty(handle, inode);
3198 if (retval)
3199 goto end_rmdir;
3200 ext4_dec_count(inode: dir);
3201 ext4_update_dx_flag(inode: dir);
3202 ext4_fc_track_unlink(handle, dentry);
3203 retval = ext4_mark_inode_dirty(handle, dir);
3204
3205 /* VFS negative dentries are incompatible with Encoding and
3206 * Case-insensitiveness. Eventually we'll want avoid
3207 * invalidating the dentries here, alongside with returning the
3208 * negative dentries at ext4_lookup(), when it is better
3209 * supported by the VFS for the CI case.
3210 */
3211 if (IS_ENABLED(CONFIG_UNICODE) && IS_CASEFOLDED(dir))
3212 d_invalidate(dentry);
3213
3214end_rmdir:
3215 brelse(bh);
3216 if (handle)
3217 ext4_journal_stop(handle);
3218 return retval;
3219}
3220
3221int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
3222 struct inode *inode,
3223 struct dentry *dentry /* NULL during fast_commit recovery */)
3224{
3225 int retval = -ENOENT;
3226 struct buffer_head *bh;
3227 struct ext4_dir_entry_2 *de;
3228 handle_t *handle;
3229 int skip_remove_dentry = 0;
3230
3231 /*
3232 * Keep this outside the transaction; it may have to set up the
3233 * directory's encryption key, which isn't GFP_NOFS-safe.
3234 */
3235 bh = ext4_find_entry(dir, d_name, res_dir: &de, NULL);
3236 if (IS_ERR(ptr: bh))
3237 return PTR_ERR(ptr: bh);
3238
3239 if (!bh)
3240 return -ENOENT;
3241
3242 if (le32_to_cpu(de->inode) != inode->i_ino) {
3243 /*
3244 * It's okay if we find dont find dentry which matches
3245 * the inode. That's because it might have gotten
3246 * renamed to a different inode number
3247 */
3248 if (EXT4_SB(sb: inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
3249 skip_remove_dentry = 1;
3250 else
3251 goto out_bh;
3252 }
3253
3254 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3255 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3256 if (IS_ERR(ptr: handle)) {
3257 retval = PTR_ERR(ptr: handle);
3258 goto out_bh;
3259 }
3260
3261 if (IS_DIRSYNC(dir))
3262 ext4_handle_sync(handle);
3263
3264 if (!skip_remove_dentry) {
3265 retval = ext4_delete_entry(handle, dir, de_del: de, bh);
3266 if (retval)
3267 goto out_handle;
3268 inode_set_mtime_to_ts(inode: dir, ts: inode_set_ctime_current(inode: dir));
3269 ext4_update_dx_flag(inode: dir);
3270 retval = ext4_mark_inode_dirty(handle, dir);
3271 if (retval)
3272 goto out_handle;
3273 } else {
3274 retval = 0;
3275 }
3276 if (inode->i_nlink == 0)
3277 ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
3278 d_name->len, d_name->name);
3279 else
3280 drop_nlink(inode);
3281 if (!inode->i_nlink)
3282 ext4_orphan_add(handle, inode);
3283 inode_set_ctime_current(inode);
3284 retval = ext4_mark_inode_dirty(handle, inode);
3285 if (dentry && !retval)
3286 ext4_fc_track_unlink(handle, dentry);
3287out_handle:
3288 ext4_journal_stop(handle);
3289out_bh:
3290 brelse(bh);
3291 return retval;
3292}
3293
3294static int ext4_unlink(struct inode *dir, struct dentry *dentry)
3295{
3296 int retval;
3297
3298 retval = ext4_emergency_state(sb: dir->i_sb);
3299 if (unlikely(retval))
3300 return retval;
3301
3302 trace_ext4_unlink_enter(parent: dir, dentry);
3303 /*
3304 * Initialize quotas before so that eventual writes go
3305 * in separate transaction
3306 */
3307 retval = dquot_initialize(inode: dir);
3308 if (retval)
3309 goto out_trace;
3310 retval = dquot_initialize(inode: d_inode(dentry));
3311 if (retval)
3312 goto out_trace;
3313
3314 retval = __ext4_unlink(dir, d_name: &dentry->d_name, inode: d_inode(dentry), dentry);
3315
3316 /* VFS negative dentries are incompatible with Encoding and
3317 * Case-insensitiveness. Eventually we'll want avoid
3318 * invalidating the dentries here, alongside with returning the
3319 * negative dentries at ext4_lookup(), when it is better
3320 * supported by the VFS for the CI case.
3321 */
3322 if (IS_ENABLED(CONFIG_UNICODE) && IS_CASEFOLDED(dir))
3323 d_invalidate(dentry);
3324
3325out_trace:
3326 trace_ext4_unlink_exit(dentry, ret: retval);
3327 return retval;
3328}
3329
3330static int ext4_init_symlink_block(handle_t *handle, struct inode *inode,
3331 struct fscrypt_str *disk_link)
3332{
3333 struct buffer_head *bh;
3334 char *kaddr;
3335 int err = 0;
3336
3337 bh = ext4_bread(handle, inode, 0, EXT4_GET_BLOCKS_CREATE);
3338 if (IS_ERR(ptr: bh))
3339 return PTR_ERR(ptr: bh);
3340
3341 BUFFER_TRACE(bh, "get_write_access");
3342 err = ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE);
3343 if (err)
3344 goto out;
3345
3346 kaddr = (char *)bh->b_data;
3347 memcpy(to: kaddr, from: disk_link->name, len: disk_link->len);
3348 inode->i_size = disk_link->len - 1;
3349 EXT4_I(inode)->i_disksize = inode->i_size;
3350 err = ext4_handle_dirty_metadata(handle, inode, bh);
3351out:
3352 brelse(bh);
3353 return err;
3354}
3355
3356static int ext4_symlink(struct mnt_idmap *idmap, struct inode *dir,
3357 struct dentry *dentry, const char *symname)
3358{
3359 handle_t *handle;
3360 struct inode *inode;
3361 int err, len = strlen(symname);
3362 int credits;
3363 struct fscrypt_str disk_link;
3364 int retries = 0;
3365
3366 err = ext4_emergency_state(sb: dir->i_sb);
3367 if (unlikely(err))
3368 return err;
3369
3370 err = fscrypt_prepare_symlink(dir, target: symname, len, max_len: dir->i_sb->s_blocksize,
3371 disk_link: &disk_link);
3372 if (err)
3373 return err;
3374
3375 err = dquot_initialize(inode: dir);
3376 if (err)
3377 return err;
3378
3379 /*
3380 * EXT4_INDEX_EXTRA_TRANS_BLOCKS for addition of entry into the
3381 * directory. +3 for inode, inode bitmap, group descriptor allocation.
3382 * EXT4_DATA_TRANS_BLOCKS for the data block allocation and
3383 * modification.
3384 */
3385 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3386 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
3387retry:
3388 inode = ext4_new_inode_start_handle(idmap, dir, S_IFLNK|S_IRWXUGO,
3389 &dentry->d_name, 0, NULL,
3390 EXT4_HT_DIR, credits);
3391 handle = ext4_journal_current_handle();
3392 if (IS_ERR(ptr: inode)) {
3393 if (handle)
3394 ext4_journal_stop(handle);
3395 err = PTR_ERR(ptr: inode);
3396 goto out_retry;
3397 }
3398
3399 if (IS_ENCRYPTED(inode)) {
3400 err = fscrypt_encrypt_symlink(inode, target: symname, len, disk_link: &disk_link);
3401 if (err)
3402 goto err_drop_inode;
3403 inode->i_op = &ext4_encrypted_symlink_inode_operations;
3404 } else {
3405 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3406 inode->i_op = &ext4_symlink_inode_operations;
3407 } else {
3408 inode->i_op = &ext4_fast_symlink_inode_operations;
3409 }
3410 }
3411
3412 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3413 /* alloc symlink block and fill it */
3414 err = ext4_init_symlink_block(handle, inode, disk_link: &disk_link);
3415 if (err)
3416 goto err_drop_inode;
3417 } else {
3418 /* clear the extent format for fast symlink */
3419 ext4_clear_inode_flag(inode, bit: EXT4_INODE_EXTENTS);
3420 memcpy(to: (char *)&EXT4_I(inode)->i_data, from: disk_link.name,
3421 len: disk_link.len);
3422 inode->i_size = disk_link.len - 1;
3423 EXT4_I(inode)->i_disksize = inode->i_size;
3424 if (!IS_ENCRYPTED(inode))
3425 inode_set_cached_link(inode, link: (char *)&EXT4_I(inode)->i_data,
3426 linklen: inode->i_size);
3427 }
3428 err = ext4_add_nondir(handle, dentry, inodep: &inode);
3429 if (handle)
3430 ext4_journal_stop(handle);
3431 iput(inode);
3432 goto out_retry;
3433
3434err_drop_inode:
3435 clear_nlink(inode);
3436 ext4_mark_inode_dirty(handle, inode);
3437 ext4_orphan_add(handle, inode);
3438 unlock_new_inode(inode);
3439 if (handle)
3440 ext4_journal_stop(handle);
3441 iput(inode);
3442out_retry:
3443 if (err == -ENOSPC && ext4_should_retry_alloc(sb: dir->i_sb, retries: &retries))
3444 goto retry;
3445 if (disk_link.name != (unsigned char *)symname)
3446 kfree(objp: disk_link.name);
3447 return err;
3448}
3449
3450int __ext4_link(struct inode *dir, struct inode *inode, struct dentry *dentry)
3451{
3452 handle_t *handle;
3453 int err, retries = 0;
3454retry:
3455 handle = ext4_journal_start(dir, EXT4_HT_DIR,
3456 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3457 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
3458 if (IS_ERR(ptr: handle))
3459 return PTR_ERR(ptr: handle);
3460
3461 if (IS_DIRSYNC(dir))
3462 ext4_handle_sync(handle);
3463
3464 inode_set_ctime_current(inode);
3465 ext4_inc_count(inode);
3466 ihold(inode);
3467
3468 err = ext4_add_entry(handle, dentry, inode);
3469 if (!err) {
3470 err = ext4_mark_inode_dirty(handle, inode);
3471 /* this can happen only for tmpfile being
3472 * linked the first time
3473 */
3474 if (inode->i_nlink == 1)
3475 ext4_orphan_del(handle, inode);
3476 d_instantiate(dentry, inode);
3477 ext4_fc_track_link(handle, dentry);
3478 } else {
3479 drop_nlink(inode);
3480 iput(inode);
3481 }
3482 ext4_journal_stop(handle);
3483 if (err == -ENOSPC && ext4_should_retry_alloc(sb: dir->i_sb, retries: &retries))
3484 goto retry;
3485 return err;
3486}
3487
3488static int ext4_link(struct dentry *old_dentry,
3489 struct inode *dir, struct dentry *dentry)
3490{
3491 struct inode *inode = d_inode(dentry: old_dentry);
3492 int err;
3493
3494 if (inode->i_nlink >= EXT4_LINK_MAX)
3495 return -EMLINK;
3496
3497 err = fscrypt_prepare_link(old_dentry, dir, dentry);
3498 if (err)
3499 return err;
3500
3501 if ((ext4_test_inode_flag(inode: dir, bit: EXT4_INODE_PROJINHERIT)) &&
3502 (!projid_eq(EXT4_I(dir)->i_projid,
3503 EXT4_I(old_dentry->d_inode)->i_projid)))
3504 return -EXDEV;
3505
3506 err = dquot_initialize(inode: dir);
3507 if (err)
3508 return err;
3509 return __ext4_link(dir, inode, dentry);
3510}
3511
3512/*
3513 * Try to find buffer head where contains the parent block.
3514 * It should be the inode block if it is inlined or the 1st block
3515 * if it is a normal dir.
3516 */
3517static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
3518 struct inode *inode,
3519 int *retval,
3520 struct ext4_dir_entry_2 **parent_de,
3521 int *inlined)
3522{
3523 struct buffer_head *bh;
3524
3525 if (!ext4_has_inline_data(inode)) {
3526 struct ext4_dir_entry_2 *de;
3527 unsigned int offset;
3528
3529 bh = ext4_read_dirblock(inode, 0, EITHER);
3530 if (IS_ERR(ptr: bh)) {
3531 *retval = PTR_ERR(ptr: bh);
3532 return NULL;
3533 }
3534
3535 de = (struct ext4_dir_entry_2 *) bh->b_data;
3536 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data,
3537 bh->b_size, 0) ||
3538 le32_to_cpu(de->inode) != inode->i_ino ||
3539 de->name_len != 1 || de->name[0] != '.') {
3540 EXT4_ERROR_INODE(inode, "directory missing '.'");
3541 brelse(bh);
3542 *retval = -EFSCORRUPTED;
3543 return NULL;
3544 }
3545 offset = ext4_rec_len_from_disk(dlen: de->rec_len,
3546 blocksize: inode->i_sb->s_blocksize);
3547 de = ext4_next_entry(p: de, blocksize: inode->i_sb->s_blocksize);
3548 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data,
3549 bh->b_size, offset) ||
3550 le32_to_cpu(de->inode) == 0 || de->name_len != 2 ||
3551 de->name[0] != '.' || de->name[1] != '.') {
3552 EXT4_ERROR_INODE(inode, "directory missing '..'");
3553 brelse(bh);
3554 *retval = -EFSCORRUPTED;
3555 return NULL;
3556 }
3557 *parent_de = de;
3558
3559 return bh;
3560 }
3561
3562 *inlined = 1;
3563 return ext4_get_first_inline_block(inode, parent_de, retval);
3564}
3565
3566struct ext4_renament {
3567 struct inode *dir;
3568 struct dentry *dentry;
3569 struct inode *inode;
3570 bool is_dir;
3571 int dir_nlink_delta;
3572
3573 /* entry for "dentry" */
3574 struct buffer_head *bh;
3575 struct ext4_dir_entry_2 *de;
3576 int inlined;
3577
3578 /* entry for ".." in inode if it's a directory */
3579 struct buffer_head *dir_bh;
3580 struct ext4_dir_entry_2 *parent_de;
3581 int dir_inlined;
3582};
3583
3584static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent, bool is_cross)
3585{
3586 int retval;
3587
3588 ent->is_dir = true;
3589 if (!is_cross)
3590 return 0;
3591
3592 ent->dir_bh = ext4_get_first_dir_block(handle, inode: ent->inode,
3593 retval: &retval, parent_de: &ent->parent_de,
3594 inlined: &ent->dir_inlined);
3595 if (!ent->dir_bh)
3596 return retval;
3597 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
3598 return -EFSCORRUPTED;
3599 BUFFER_TRACE(ent->dir_bh, "get_write_access");
3600 return ext4_journal_get_write_access(handle, ent->dir->i_sb,
3601 ent->dir_bh, EXT4_JTR_NONE);
3602}
3603
3604static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
3605 unsigned dir_ino)
3606{
3607 int retval;
3608
3609 if (!ent->dir_bh)
3610 return 0;
3611
3612 ent->parent_de->inode = cpu_to_le32(dir_ino);
3613 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
3614 if (!ent->dir_inlined) {
3615 if (is_dx(ent->inode)) {
3616 retval = ext4_handle_dirty_dx_node(handle,
3617 inode: ent->inode,
3618 bh: ent->dir_bh);
3619 } else {
3620 retval = ext4_handle_dirty_dirblock(handle, inode: ent->inode,
3621 bh: ent->dir_bh);
3622 }
3623 } else {
3624 retval = ext4_mark_inode_dirty(handle, ent->inode);
3625 }
3626 if (retval) {
3627 ext4_std_error(ent->dir->i_sb, retval);
3628 return retval;
3629 }
3630 return 0;
3631}
3632
3633static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
3634 unsigned ino, unsigned file_type)
3635{
3636 int retval, retval2;
3637
3638 BUFFER_TRACE(ent->bh, "get write access");
3639 retval = ext4_journal_get_write_access(handle, ent->dir->i_sb, ent->bh,
3640 EXT4_JTR_NONE);
3641 if (retval)
3642 return retval;
3643 ent->de->inode = cpu_to_le32(ino);
3644 if (ext4_has_feature_filetype(sb: ent->dir->i_sb))
3645 ent->de->file_type = file_type;
3646 inode_inc_iversion(inode: ent->dir);
3647 inode_set_mtime_to_ts(inode: ent->dir, ts: inode_set_ctime_current(inode: ent->dir));
3648 retval = ext4_mark_inode_dirty(handle, ent->dir);
3649 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
3650 if (!ent->inlined) {
3651 retval2 = ext4_handle_dirty_dirblock(handle, inode: ent->dir, bh: ent->bh);
3652 if (unlikely(retval2)) {
3653 ext4_std_error(ent->dir->i_sb, retval2);
3654 return retval2;
3655 }
3656 }
3657 return retval;
3658}
3659
3660static void ext4_resetent(handle_t *handle, struct ext4_renament *ent,
3661 unsigned ino, unsigned file_type)
3662{
3663 struct ext4_renament old = *ent;
3664 int retval = 0;
3665
3666 /*
3667 * old->de could have moved from under us during make indexed dir,
3668 * so the old->de may no longer valid and need to find it again
3669 * before reset old inode info.
3670 */
3671 old.bh = ext4_find_entry(dir: old.dir, d_name: &old.dentry->d_name, res_dir: &old.de,
3672 inlined: &old.inlined);
3673 if (IS_ERR(ptr: old.bh))
3674 retval = PTR_ERR(ptr: old.bh);
3675 if (!old.bh)
3676 retval = -ENOENT;
3677 if (retval) {
3678 ext4_std_error(old.dir->i_sb, retval);
3679 return;
3680 }
3681
3682 ext4_setent(handle, ent: &old, ino, file_type);
3683 brelse(bh: old.bh);
3684}
3685
3686static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
3687 const struct qstr *d_name)
3688{
3689 int retval = -ENOENT;
3690 struct buffer_head *bh;
3691 struct ext4_dir_entry_2 *de;
3692
3693 bh = ext4_find_entry(dir, d_name, res_dir: &de, NULL);
3694 if (IS_ERR(ptr: bh))
3695 return PTR_ERR(ptr: bh);
3696 if (bh) {
3697 retval = ext4_delete_entry(handle, dir, de_del: de, bh);
3698 brelse(bh);
3699 }
3700 return retval;
3701}
3702
3703static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent,
3704 int force_reread)
3705{
3706 int retval;
3707 /*
3708 * ent->de could have moved from under us during htree split, so make
3709 * sure that we are deleting the right entry. We might also be pointing
3710 * to a stale entry in the unused part of ent->bh so just checking inum
3711 * and the name isn't enough.
3712 */
3713 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
3714 ent->de->name_len != ent->dentry->d_name.len ||
3715 strncmp(ent->de->name, ent->dentry->d_name.name,
3716 ent->de->name_len) ||
3717 force_reread) {
3718 retval = ext4_find_delete_entry(handle, dir: ent->dir,
3719 d_name: &ent->dentry->d_name);
3720 } else {
3721 retval = ext4_delete_entry(handle, dir: ent->dir, de_del: ent->de, bh: ent->bh);
3722 if (retval == -ENOENT) {
3723 retval = ext4_find_delete_entry(handle, dir: ent->dir,
3724 d_name: &ent->dentry->d_name);
3725 }
3726 }
3727
3728 if (retval) {
3729 ext4_warning_inode(ent->dir,
3730 "Deleting old file: nlink %d, error=%d",
3731 ent->dir->i_nlink, retval);
3732 }
3733}
3734
3735static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
3736{
3737 if (ent->dir_nlink_delta) {
3738 if (ent->dir_nlink_delta == -1)
3739 ext4_dec_count(inode: ent->dir);
3740 else
3741 ext4_inc_count(inode: ent->dir);
3742 ext4_mark_inode_dirty(handle, ent->dir);
3743 }
3744}
3745
3746static struct inode *ext4_whiteout_for_rename(struct mnt_idmap *idmap,
3747 struct ext4_renament *ent,
3748 int credits, handle_t **h)
3749{
3750 struct inode *wh;
3751 handle_t *handle;
3752 int retries = 0;
3753
3754 /*
3755 * for inode block, sb block, group summaries,
3756 * and inode bitmap
3757 */
3758 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
3759 EXT4_XATTR_TRANS_BLOCKS + 4);
3760retry:
3761 wh = ext4_new_inode_start_handle(idmap, ent->dir,
3762 S_IFCHR | WHITEOUT_MODE,
3763 &ent->dentry->d_name, 0, NULL,
3764 EXT4_HT_DIR, credits);
3765
3766 handle = ext4_journal_current_handle();
3767 if (IS_ERR(ptr: wh)) {
3768 if (handle)
3769 ext4_journal_stop(handle);
3770 if (PTR_ERR(ptr: wh) == -ENOSPC &&
3771 ext4_should_retry_alloc(sb: ent->dir->i_sb, retries: &retries))
3772 goto retry;
3773 } else {
3774 *h = handle;
3775 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);
3776 wh->i_op = &ext4_special_inode_operations;
3777 }
3778 return wh;
3779}
3780
3781/*
3782 * Anybody can rename anything with this: the permission checks are left to the
3783 * higher-level routines.
3784 *
3785 * n.b. old_{dentry,inode) refers to the source dentry/inode
3786 * while new_{dentry,inode) refers to the destination dentry/inode
3787 * This comes from rename(const char *oldpath, const char *newpath)
3788 */
3789static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir,
3790 struct dentry *old_dentry, struct inode *new_dir,
3791 struct dentry *new_dentry, unsigned int flags)
3792{
3793 handle_t *handle = NULL;
3794 struct ext4_renament old = {
3795 .dir = old_dir,
3796 .dentry = old_dentry,
3797 .inode = d_inode(dentry: old_dentry),
3798 };
3799 struct ext4_renament new = {
3800 .dir = new_dir,
3801 .dentry = new_dentry,
3802 .inode = d_inode(dentry: new_dentry),
3803 };
3804 int force_reread;
3805 int retval;
3806 struct inode *whiteout = NULL;
3807 int credits;
3808 u8 old_file_type;
3809
3810 if (new.inode && new.inode->i_nlink == 0) {
3811 EXT4_ERROR_INODE(new.inode,
3812 "target of rename is already freed");
3813 return -EFSCORRUPTED;
3814 }
3815
3816 if ((ext4_test_inode_flag(inode: new_dir, bit: EXT4_INODE_PROJINHERIT)) &&
3817 (!projid_eq(EXT4_I(new_dir)->i_projid,
3818 EXT4_I(old_dentry->d_inode)->i_projid)))
3819 return -EXDEV;
3820
3821 retval = dquot_initialize(inode: old.dir);
3822 if (retval)
3823 return retval;
3824 retval = dquot_initialize(inode: old.inode);
3825 if (retval)
3826 return retval;
3827 retval = dquot_initialize(inode: new.dir);
3828 if (retval)
3829 return retval;
3830
3831 /* Initialize quotas before so that eventual writes go
3832 * in separate transaction */
3833 if (new.inode) {
3834 retval = dquot_initialize(inode: new.inode);
3835 if (retval)
3836 return retval;
3837 }
3838
3839 old.bh = ext4_find_entry(dir: old.dir, d_name: &old.dentry->d_name, res_dir: &old.de,
3840 inlined: &old.inlined);
3841 if (IS_ERR(ptr: old.bh))
3842 return PTR_ERR(ptr: old.bh);
3843
3844 /*
3845 * Check for inode number is _not_ due to possible IO errors.
3846 * We might rmdir the source, keep it as pwd of some process
3847 * and merrily kill the link to whatever was created under the
3848 * same name. Goodbye sticky bit ;-<
3849 */
3850 retval = -ENOENT;
3851 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3852 goto release_bh;
3853
3854 new.bh = ext4_find_entry(dir: new.dir, d_name: &new.dentry->d_name,
3855 res_dir: &new.de, inlined: &new.inlined);
3856 if (IS_ERR(ptr: new.bh)) {
3857 retval = PTR_ERR(ptr: new.bh);
3858 new.bh = NULL;
3859 goto release_bh;
3860 }
3861 if (new.bh) {
3862 if (!new.inode) {
3863 brelse(bh: new.bh);
3864 new.bh = NULL;
3865 }
3866 }
3867 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
3868 ext4_alloc_da_blocks(inode: old.inode);
3869
3870 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3871 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
3872 if (!(flags & RENAME_WHITEOUT)) {
3873 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);
3874 if (IS_ERR(ptr: handle)) {
3875 retval = PTR_ERR(ptr: handle);
3876 goto release_bh;
3877 }
3878 } else {
3879 whiteout = ext4_whiteout_for_rename(idmap, ent: &old, credits, h: &handle);
3880 if (IS_ERR(ptr: whiteout)) {
3881 retval = PTR_ERR(ptr: whiteout);
3882 goto release_bh;
3883 }
3884 }
3885
3886 old_file_type = old.de->file_type;
3887 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3888 ext4_handle_sync(handle);
3889
3890 if (S_ISDIR(old.inode->i_mode)) {
3891 if (new.inode) {
3892 retval = -ENOTEMPTY;
3893 if (!ext4_empty_dir(inode: new.inode))
3894 goto end_rename;
3895 } else {
3896 retval = -EMLINK;
3897 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
3898 goto end_rename;
3899 }
3900 retval = ext4_rename_dir_prepare(handle, ent: &old, is_cross: new.dir != old.dir);
3901 if (retval)
3902 goto end_rename;
3903 }
3904 /*
3905 * If we're renaming a file within an inline_data dir and adding or
3906 * setting the new dirent causes a conversion from inline_data to
3907 * extents/blockmap, we need to force the dirent delete code to
3908 * re-read the directory, or else we end up trying to delete a dirent
3909 * from what is now the extent tree root (or a block map).
3910 */
3911 force_reread = (new.dir->i_ino == old.dir->i_ino &&
3912 ext4_test_inode_flag(inode: new.dir, bit: EXT4_INODE_INLINE_DATA));
3913
3914 if (whiteout) {
3915 /*
3916 * Do this before adding a new entry, so the old entry is sure
3917 * to be still pointing to the valid old entry.
3918 */
3919 retval = ext4_setent(handle, ent: &old, ino: whiteout->i_ino,
3920 EXT4_FT_CHRDEV);
3921 if (retval)
3922 goto end_rename;
3923 retval = ext4_mark_inode_dirty(handle, whiteout);
3924 if (unlikely(retval))
3925 goto end_rename;
3926
3927 }
3928 if (!new.bh) {
3929 retval = ext4_add_entry(handle, dentry: new.dentry, inode: old.inode);
3930 if (retval)
3931 goto end_rename;
3932 } else {
3933 retval = ext4_setent(handle, ent: &new,
3934 ino: old.inode->i_ino, file_type: old_file_type);
3935 if (retval)
3936 goto end_rename;
3937 }
3938 if (force_reread)
3939 force_reread = !ext4_test_inode_flag(inode: new.dir,
3940 bit: EXT4_INODE_INLINE_DATA);
3941
3942 /*
3943 * Like most other Unix systems, set the ctime for inodes on a
3944 * rename.
3945 */
3946 inode_set_ctime_current(inode: old.inode);
3947 retval = ext4_mark_inode_dirty(handle, old.inode);
3948 if (unlikely(retval))
3949 goto end_rename;
3950
3951 if (!whiteout) {
3952 /*
3953 * ok, that's it
3954 */
3955 ext4_rename_delete(handle, ent: &old, force_reread);
3956 }
3957
3958 if (new.inode) {
3959 ext4_dec_count(inode: new.inode);
3960 inode_set_ctime_current(inode: new.inode);
3961 }
3962 inode_set_mtime_to_ts(inode: old.dir, ts: inode_set_ctime_current(inode: old.dir));
3963 ext4_update_dx_flag(inode: old.dir);
3964 if (old.is_dir) {
3965 retval = ext4_rename_dir_finish(handle, ent: &old, dir_ino: new.dir->i_ino);
3966 if (retval)
3967 goto end_rename;
3968
3969 ext4_dec_count(inode: old.dir);
3970 if (new.inode) {
3971 /* checked ext4_empty_dir above, can't have another
3972 * parent, ext4_dec_count() won't work for many-linked
3973 * dirs */
3974 clear_nlink(inode: new.inode);
3975 } else {
3976 ext4_inc_count(inode: new.dir);
3977 ext4_update_dx_flag(inode: new.dir);
3978 retval = ext4_mark_inode_dirty(handle, new.dir);
3979 if (unlikely(retval))
3980 goto end_rename;
3981 }
3982 }
3983 retval = ext4_mark_inode_dirty(handle, old.dir);
3984 if (unlikely(retval))
3985 goto end_rename;
3986
3987 if (old.is_dir) {
3988 /*
3989 * We disable fast commits here that's because the
3990 * replay code is not yet capable of changing dot dot
3991 * dirents in directories.
3992 */
3993 ext4_fc_mark_ineligible(sb: old.inode->i_sb,
3994 reason: EXT4_FC_REASON_RENAME_DIR, handle);
3995 } else {
3996 struct super_block *sb = old.inode->i_sb;
3997
3998 if (new.inode)
3999 ext4_fc_track_unlink(handle, dentry: new.dentry);
4000 if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4001 !(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY) &&
4002 !(ext4_test_mount_flag(sb, bit: EXT4_MF_FC_INELIGIBLE))) {
4003 __ext4_fc_track_link(handle, inode: old.inode, dentry: new.dentry);
4004 __ext4_fc_track_unlink(handle, inode: old.inode, dentry: old.dentry);
4005 if (whiteout)
4006 __ext4_fc_track_create(handle, inode: whiteout,
4007 dentry: old.dentry);
4008 }
4009 }
4010
4011 if (new.inode) {
4012 retval = ext4_mark_inode_dirty(handle, new.inode);
4013 if (unlikely(retval))
4014 goto end_rename;
4015 if (!new.inode->i_nlink)
4016 ext4_orphan_add(handle, new.inode);
4017 }
4018 retval = 0;
4019
4020end_rename:
4021 if (whiteout) {
4022 if (retval) {
4023 ext4_resetent(handle, ent: &old,
4024 ino: old.inode->i_ino, file_type: old_file_type);
4025 drop_nlink(inode: whiteout);
4026 ext4_mark_inode_dirty(handle, whiteout);
4027 ext4_orphan_add(handle, whiteout);
4028 }
4029 unlock_new_inode(whiteout);
4030 ext4_journal_stop(handle);
4031 iput(whiteout);
4032 } else {
4033 ext4_journal_stop(handle);
4034 }
4035release_bh:
4036 brelse(bh: old.dir_bh);
4037 brelse(bh: old.bh);
4038 brelse(bh: new.bh);
4039
4040 return retval;
4041}
4042
4043static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
4044 struct inode *new_dir, struct dentry *new_dentry)
4045{
4046 handle_t *handle = NULL;
4047 struct ext4_renament old = {
4048 .dir = old_dir,
4049 .dentry = old_dentry,
4050 .inode = d_inode(dentry: old_dentry),
4051 };
4052 struct ext4_renament new = {
4053 .dir = new_dir,
4054 .dentry = new_dentry,
4055 .inode = d_inode(dentry: new_dentry),
4056 };
4057 u8 new_file_type;
4058 int retval;
4059
4060 if ((ext4_test_inode_flag(inode: new_dir, bit: EXT4_INODE_PROJINHERIT) &&
4061 !projid_eq(EXT4_I(new_dir)->i_projid,
4062 EXT4_I(old_dentry->d_inode)->i_projid)) ||
4063 (ext4_test_inode_flag(inode: old_dir, bit: EXT4_INODE_PROJINHERIT) &&
4064 !projid_eq(EXT4_I(old_dir)->i_projid,
4065 EXT4_I(new_dentry->d_inode)->i_projid)))
4066 return -EXDEV;
4067
4068 retval = dquot_initialize(inode: old.dir);
4069 if (retval)
4070 return retval;
4071 retval = dquot_initialize(inode: new.dir);
4072 if (retval)
4073 return retval;
4074
4075 old.bh = ext4_find_entry(dir: old.dir, d_name: &old.dentry->d_name,
4076 res_dir: &old.de, inlined: &old.inlined);
4077 if (IS_ERR(ptr: old.bh))
4078 return PTR_ERR(ptr: old.bh);
4079 /*
4080 * Check for inode number is _not_ due to possible IO errors.
4081 * We might rmdir the source, keep it as pwd of some process
4082 * and merrily kill the link to whatever was created under the
4083 * same name. Goodbye sticky bit ;-<
4084 */
4085 retval = -ENOENT;
4086 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
4087 goto end_rename;
4088
4089 new.bh = ext4_find_entry(dir: new.dir, d_name: &new.dentry->d_name,
4090 res_dir: &new.de, inlined: &new.inlined);
4091 if (IS_ERR(ptr: new.bh)) {
4092 retval = PTR_ERR(ptr: new.bh);
4093 new.bh = NULL;
4094 goto end_rename;
4095 }
4096
4097 /* RENAME_EXCHANGE case: old *and* new must both exist */
4098 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
4099 goto end_rename;
4100
4101 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
4102 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
4103 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
4104 if (IS_ERR(ptr: handle)) {
4105 retval = PTR_ERR(ptr: handle);
4106 handle = NULL;
4107 goto end_rename;
4108 }
4109
4110 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
4111 ext4_handle_sync(handle);
4112
4113 if (S_ISDIR(old.inode->i_mode)) {
4114 retval = ext4_rename_dir_prepare(handle, ent: &old, is_cross: new.dir != old.dir);
4115 if (retval)
4116 goto end_rename;
4117 }
4118 if (S_ISDIR(new.inode->i_mode)) {
4119 retval = ext4_rename_dir_prepare(handle, ent: &new, is_cross: new.dir != old.dir);
4120 if (retval)
4121 goto end_rename;
4122 }
4123
4124 /*
4125 * Other than the special case of overwriting a directory, parents'
4126 * nlink only needs to be modified if this is a cross directory rename.
4127 */
4128 if (old.dir != new.dir && old.is_dir != new.is_dir) {
4129 old.dir_nlink_delta = old.is_dir ? -1 : 1;
4130 new.dir_nlink_delta = -old.dir_nlink_delta;
4131 retval = -EMLINK;
4132 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
4133 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
4134 goto end_rename;
4135 }
4136
4137 new_file_type = new.de->file_type;
4138 retval = ext4_setent(handle, ent: &new, ino: old.inode->i_ino, file_type: old.de->file_type);
4139 if (retval)
4140 goto end_rename;
4141
4142 retval = ext4_setent(handle, ent: &old, ino: new.inode->i_ino, file_type: new_file_type);
4143 if (retval)
4144 goto end_rename;
4145
4146 /*
4147 * Like most other Unix systems, set the ctime for inodes on a
4148 * rename.
4149 */
4150 inode_set_ctime_current(inode: old.inode);
4151 inode_set_ctime_current(inode: new.inode);
4152 retval = ext4_mark_inode_dirty(handle, old.inode);
4153 if (unlikely(retval))
4154 goto end_rename;
4155 retval = ext4_mark_inode_dirty(handle, new.inode);
4156 if (unlikely(retval))
4157 goto end_rename;
4158 ext4_fc_mark_ineligible(sb: new.inode->i_sb,
4159 reason: EXT4_FC_REASON_CROSS_RENAME, handle);
4160 if (old.dir_bh) {
4161 retval = ext4_rename_dir_finish(handle, ent: &old, dir_ino: new.dir->i_ino);
4162 if (retval)
4163 goto end_rename;
4164 }
4165 if (new.dir_bh) {
4166 retval = ext4_rename_dir_finish(handle, ent: &new, dir_ino: old.dir->i_ino);
4167 if (retval)
4168 goto end_rename;
4169 }
4170 ext4_update_dir_count(handle, ent: &old);
4171 ext4_update_dir_count(handle, ent: &new);
4172 retval = 0;
4173
4174end_rename:
4175 brelse(bh: old.dir_bh);
4176 brelse(bh: new.dir_bh);
4177 brelse(bh: old.bh);
4178 brelse(bh: new.bh);
4179 if (handle)
4180 ext4_journal_stop(handle);
4181 return retval;
4182}
4183
4184static int ext4_rename2(struct mnt_idmap *idmap,
4185 struct inode *old_dir, struct dentry *old_dentry,
4186 struct inode *new_dir, struct dentry *new_dentry,
4187 unsigned int flags)
4188{
4189 int err;
4190
4191 err = ext4_emergency_state(sb: old_dir->i_sb);
4192 if (unlikely(err))
4193 return err;
4194
4195 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
4196 return -EINVAL;
4197
4198 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
4199 flags);
4200 if (err)
4201 return err;
4202
4203 if (flags & RENAME_EXCHANGE) {
4204 return ext4_cross_rename(old_dir, old_dentry,
4205 new_dir, new_dentry);
4206 }
4207
4208 return ext4_rename(idmap, old_dir, old_dentry, new_dir, new_dentry, flags);
4209}
4210
4211/*
4212 * directories can handle most operations...
4213 */
4214const struct inode_operations ext4_dir_inode_operations = {
4215 .create = ext4_create,
4216 .lookup = ext4_lookup,
4217 .link = ext4_link,
4218 .unlink = ext4_unlink,
4219 .symlink = ext4_symlink,
4220 .mkdir = ext4_mkdir,
4221 .rmdir = ext4_rmdir,
4222 .mknod = ext4_mknod,
4223 .tmpfile = ext4_tmpfile,
4224 .rename = ext4_rename2,
4225 .setattr = ext4_setattr,
4226 .getattr = ext4_getattr,
4227 .listxattr = ext4_listxattr,
4228 .get_inode_acl = ext4_get_acl,
4229 .set_acl = ext4_set_acl,
4230 .fiemap = ext4_fiemap,
4231 .fileattr_get = ext4_fileattr_get,
4232 .fileattr_set = ext4_fileattr_set,
4233};
4234
4235const struct inode_operations ext4_special_inode_operations = {
4236 .setattr = ext4_setattr,
4237 .getattr = ext4_getattr,
4238 .listxattr = ext4_listxattr,
4239 .get_inode_acl = ext4_get_acl,
4240 .set_acl = ext4_set_acl,
4241};
4242