Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * linux/fs/ext4/namei.c
4 : *
5 : * Copyright (C) 1992, 1993, 1994, 1995
6 : * Remy Card (card@masi.ibp.fr)
7 : * Laboratoire MASI - Institut Blaise Pascal
8 : * Universite Pierre et Marie Curie (Paris VI)
9 : *
10 : * from
11 : *
12 : * linux/fs/minix/namei.c
13 : *
14 : * Copyright (C) 1991, 1992 Linus Torvalds
15 : *
16 : * Big-endian to little-endian byte-swapping/bitmaps by
17 : * David S. Miller (davem@caip.rutgers.edu), 1995
18 : * Directory entry file type support and forward compatibility hooks
19 : * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
20 : * Hash Tree Directory indexing (c)
21 : * Daniel Phillips, 2001
22 : * Hash Tree Directory indexing porting
23 : * Christopher Li, 2002
24 : * Hash Tree Directory indexing cleanup
25 : * Theodore Ts'o, 2002
26 : */
27 :
28 : #include <linux/fs.h>
29 : #include <linux/pagemap.h>
30 : #include <linux/time.h>
31 : #include <linux/fcntl.h>
32 : #include <linux/stat.h>
33 : #include <linux/string.h>
34 : #include <linux/quotaops.h>
35 : #include <linux/buffer_head.h>
36 : #include <linux/bio.h>
37 : #include <linux/iversion.h>
38 : #include <linux/unicode.h>
39 : #include "ext4.h"
40 : #include "ext4_jbd2.h"
41 :
42 : #include "xattr.h"
43 : #include "acl.h"
44 :
45 : #include <trace/events/ext4.h>
46 : /*
47 : * define how far ahead to read directories while searching them.
48 : */
49 : #define NAMEI_RA_CHUNKS 2
50 : #define NAMEI_RA_BLOCKS 4
51 : #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
52 :
53 173 : static struct buffer_head *ext4_append(handle_t *handle,
54 : struct inode *inode,
55 : ext4_lblk_t *block)
56 : {
57 173 : struct buffer_head *bh;
58 173 : int err;
59 :
60 173 : if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
61 : ((inode->i_size >> 10) >=
62 : EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
63 173 : return ERR_PTR(-ENOSPC);
64 :
65 173 : *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
66 :
67 173 : bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE);
68 173 : if (IS_ERR(bh))
69 : return bh;
70 173 : inode->i_size += inode->i_sb->s_blocksize;
71 173 : EXT4_I(inode)->i_disksize = inode->i_size;
72 173 : BUFFER_TRACE(bh, "get_write_access");
73 173 : err = ext4_journal_get_write_access(handle, bh);
74 173 : if (err) {
75 0 : brelse(bh);
76 0 : ext4_std_error(inode->i_sb, err);
77 0 : return ERR_PTR(err);
78 : }
79 : return bh;
80 : }
81 :
82 : static int ext4_dx_csum_verify(struct inode *inode,
83 : struct ext4_dir_entry *dirent);
84 :
85 : /*
86 : * Hints to ext4_read_dirblock regarding whether we expect a directory
87 : * block being read to be an index block, or a block containing
88 : * directory entries (and if the latter, whether it was found via a
89 : * logical block in an htree index block). This is used to control
90 : * what sort of sanity checkinig ext4_read_dirblock() will do on the
91 : * directory block read from the storage device. EITHER will means
92 : * the caller doesn't know what kind of directory block will be read,
93 : * so no specific verification will be done.
94 : */
95 : typedef enum {
96 : EITHER, INDEX, DIRENT, DIRENT_HTREE
97 : } dirblock_type_t;
98 :
99 : #define ext4_read_dirblock(inode, block, type) \
100 : __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__)
101 :
102 7994 : static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
103 : ext4_lblk_t block,
104 : dirblock_type_t type,
105 : const char *func,
106 : unsigned int line)
107 : {
108 7994 : struct buffer_head *bh;
109 7994 : struct ext4_dir_entry *dirent;
110 7994 : int is_dx_block = 0;
111 :
112 7994 : if (ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_EIO))
113 : bh = ERR_PTR(-EIO);
114 : else
115 7994 : bh = ext4_bread(NULL, inode, block, 0);
116 7994 : if (IS_ERR(bh)) {
117 0 : __ext4_warning(inode->i_sb, func, line,
118 : "inode #%lu: lblock %lu: comm %s: "
119 : "error %ld reading directory block",
120 : inode->i_ino, (unsigned long)block,
121 0 : current->comm, PTR_ERR(bh));
122 :
123 0 : return bh;
124 : }
125 7994 : if (!bh && (type == INDEX || type == DIRENT_HTREE)) {
126 0 : ext4_error_inode(inode, func, line, block,
127 : "Directory hole found for htree %s block",
128 : (type == INDEX) ? "index" : "leaf");
129 0 : return ERR_PTR(-EFSCORRUPTED);
130 : }
131 7994 : if (!bh)
132 : return NULL;
133 7994 : dirent = (struct ext4_dir_entry *) bh->b_data;
134 : /* Determine whether or not we have an index block */
135 15988 : if (is_dx(inode)) {
136 6670 : if (block == 0)
137 : is_dx_block = 1;
138 3345 : else if (ext4_rec_len_from_disk(dirent->rec_len,
139 3345 : inode->i_sb->s_blocksize) ==
140 : inode->i_sb->s_blocksize)
141 32 : is_dx_block = 1;
142 : }
143 7994 : if (!is_dx_block && type == INDEX) {
144 0 : ext4_error_inode(inode, func, line, block,
145 : "directory leaf block found instead of index block");
146 0 : brelse(bh);
147 0 : return ERR_PTR(-EFSCORRUPTED);
148 : }
149 7994 : if (!ext4_has_metadata_csum(inode->i_sb) ||
150 0 : buffer_verified(bh))
151 7994 : return bh;
152 :
153 : /*
154 : * An empty leaf block can get mistaken for a index block; for
155 : * this reason, we can only check the index checksum when the
156 : * caller is sure it should be an index block.
157 : */
158 0 : if (is_dx_block && type == INDEX) {
159 0 : if (ext4_dx_csum_verify(inode, dirent) &&
160 0 : !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))
161 0 : set_buffer_verified(bh);
162 : else {
163 0 : ext4_error_inode_err(inode, func, line, block,
164 : EFSBADCRC,
165 : "Directory index failed checksum");
166 0 : brelse(bh);
167 0 : return ERR_PTR(-EFSBADCRC);
168 : }
169 : }
170 0 : if (!is_dx_block) {
171 0 : if (ext4_dirblock_csum_verify(inode, bh) &&
172 0 : !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))
173 0 : set_buffer_verified(bh);
174 : else {
175 0 : ext4_error_inode_err(inode, func, line, block,
176 : EFSBADCRC,
177 : "Directory block failed checksum");
178 0 : brelse(bh);
179 0 : return ERR_PTR(-EFSBADCRC);
180 : }
181 : }
182 : return bh;
183 : }
184 :
185 : #ifdef DX_DEBUG
186 : #define dxtrace(command) command
187 : #else
188 : #define dxtrace(command)
189 : #endif
190 :
191 : struct fake_dirent
192 : {
193 : __le32 inode;
194 : __le16 rec_len;
195 : u8 name_len;
196 : u8 file_type;
197 : };
198 :
199 : struct dx_countlimit
200 : {
201 : __le16 limit;
202 : __le16 count;
203 : };
204 :
205 : struct dx_entry
206 : {
207 : __le32 hash;
208 : __le32 block;
209 : };
210 :
211 : /*
212 : * dx_root_info is laid out so that if it should somehow get overlaid by a
213 : * dirent the two low bits of the hash version will be zero. Therefore, the
214 : * hash version mod 4 should never be 0. Sincerely, the paranoia department.
215 : */
216 :
217 : struct dx_root
218 : {
219 : struct fake_dirent dot;
220 : char dot_name[4];
221 : struct fake_dirent dotdot;
222 : char dotdot_name[4];
223 : struct dx_root_info
224 : {
225 : __le32 reserved_zero;
226 : u8 hash_version;
227 : u8 info_length; /* 8 */
228 : u8 indirect_levels;
229 : u8 unused_flags;
230 : }
231 : info;
232 : struct dx_entry entries[];
233 : };
234 :
235 : struct dx_node
236 : {
237 : struct fake_dirent fake;
238 : struct dx_entry entries[];
239 : };
240 :
241 :
242 : struct dx_frame
243 : {
244 : struct buffer_head *bh;
245 : struct dx_entry *entries;
246 : struct dx_entry *at;
247 : };
248 :
249 : struct dx_map_entry
250 : {
251 : u32 hash;
252 : u16 offs;
253 : u16 size;
254 : };
255 :
256 : /*
257 : * This goes at the end of each htree block.
258 : */
259 : struct dx_tail {
260 : u32 dt_reserved;
261 : __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
262 : };
263 :
264 : static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
265 : static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
266 : static inline unsigned dx_get_hash(struct dx_entry *entry);
267 : static void dx_set_hash(struct dx_entry *entry, unsigned value);
268 : static unsigned dx_get_count(struct dx_entry *entries);
269 : static unsigned dx_get_limit(struct dx_entry *entries);
270 : static void dx_set_count(struct dx_entry *entries, unsigned value);
271 : static void dx_set_limit(struct dx_entry *entries, unsigned value);
272 : static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
273 : static unsigned dx_node_limit(struct inode *dir);
274 : static struct dx_frame *dx_probe(struct ext4_filename *fname,
275 : struct inode *dir,
276 : struct dx_hash_info *hinfo,
277 : struct dx_frame *frame);
278 : static void dx_release(struct dx_frame *frames);
279 : static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
280 : unsigned blocksize, struct dx_hash_info *hinfo,
281 : struct dx_map_entry map[]);
282 : static void dx_sort_map(struct dx_map_entry *map, unsigned count);
283 : static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
284 : struct dx_map_entry *offsets, int count, unsigned blocksize);
285 : static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
286 : static void dx_insert_block(struct dx_frame *frame,
287 : u32 hash, ext4_lblk_t block);
288 : static int ext4_htree_next_block(struct inode *dir, __u32 hash,
289 : struct dx_frame *frame,
290 : struct dx_frame *frames,
291 : __u32 *start_hash);
292 : static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
293 : struct ext4_filename *fname,
294 : struct ext4_dir_entry_2 **res_dir);
295 : static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
296 : struct inode *dir, struct inode *inode);
297 :
298 : /* checksumming functions */
299 0 : void ext4_initialize_dirent_tail(struct buffer_head *bh,
300 : unsigned int blocksize)
301 : {
302 0 : struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
303 :
304 0 : memset(t, 0, sizeof(struct ext4_dir_entry_tail));
305 0 : t->det_rec_len = ext4_rec_len_to_disk(
306 : sizeof(struct ext4_dir_entry_tail), blocksize);
307 0 : t->det_reserved_ft = EXT4_FT_DIR_CSUM;
308 0 : }
309 :
310 : /* Walk through a dirent block to find a checksum "dirent" at the tail */
311 0 : static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
312 : struct buffer_head *bh)
313 : {
314 0 : struct ext4_dir_entry_tail *t;
315 :
316 : #ifdef PARANOID
317 : struct ext4_dir_entry *d, *top;
318 :
319 : d = (struct ext4_dir_entry *)bh->b_data;
320 : top = (struct ext4_dir_entry *)(bh->b_data +
321 : (EXT4_BLOCK_SIZE(inode->i_sb) -
322 : sizeof(struct ext4_dir_entry_tail)));
323 : while (d < top && d->rec_len)
324 : d = (struct ext4_dir_entry *)(((void *)d) +
325 : le16_to_cpu(d->rec_len));
326 :
327 : if (d != top)
328 : return NULL;
329 :
330 : t = (struct ext4_dir_entry_tail *)d;
331 : #else
332 0 : t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb));
333 : #endif
334 :
335 0 : if (t->det_reserved_zero1 ||
336 : le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
337 0 : t->det_reserved_zero2 ||
338 : t->det_reserved_ft != EXT4_FT_DIR_CSUM)
339 : return NULL;
340 :
341 : return t;
342 : }
343 :
344 0 : static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size)
345 : {
346 0 : struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
347 0 : struct ext4_inode_info *ei = EXT4_I(inode);
348 0 : __u32 csum;
349 :
350 0 : csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
351 0 : return cpu_to_le32(csum);
352 : }
353 :
354 : #define warn_no_space_for_csum(inode) \
355 : __warn_no_space_for_csum((inode), __func__, __LINE__)
356 :
357 0 : static void __warn_no_space_for_csum(struct inode *inode, const char *func,
358 : unsigned int line)
359 : {
360 0 : __ext4_warning_inode(inode, func, line,
361 : "No space for directory leaf checksum. Please run e2fsck -D.");
362 : }
363 :
364 298 : int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)
365 : {
366 298 : struct ext4_dir_entry_tail *t;
367 :
368 298 : if (!ext4_has_metadata_csum(inode->i_sb))
369 : return 1;
370 :
371 0 : t = get_dirent_tail(inode, bh);
372 0 : if (!t) {
373 0 : warn_no_space_for_csum(inode);
374 0 : return 0;
375 : }
376 :
377 0 : if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data,
378 0 : (char *)t - bh->b_data))
379 0 : return 0;
380 :
381 : return 1;
382 : }
383 :
384 1175 : static void ext4_dirblock_csum_set(struct inode *inode,
385 : struct buffer_head *bh)
386 : {
387 1175 : struct ext4_dir_entry_tail *t;
388 :
389 1175 : if (!ext4_has_metadata_csum(inode->i_sb))
390 : return;
391 :
392 0 : t = get_dirent_tail(inode, bh);
393 0 : if (!t) {
394 0 : warn_no_space_for_csum(inode);
395 0 : return;
396 : }
397 :
398 0 : t->det_checksum = ext4_dirblock_csum(inode, bh->b_data,
399 0 : (char *)t - bh->b_data);
400 : }
401 :
402 1175 : int ext4_handle_dirty_dirblock(handle_t *handle,
403 : struct inode *inode,
404 : struct buffer_head *bh)
405 : {
406 1175 : ext4_dirblock_csum_set(inode, bh);
407 1175 : return ext4_handle_dirty_metadata(handle, inode, bh);
408 : }
409 :
410 0 : static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
411 : struct ext4_dir_entry *dirent,
412 : int *offset)
413 : {
414 0 : struct ext4_dir_entry *dp;
415 0 : struct dx_root_info *root;
416 0 : int count_offset;
417 :
418 0 : if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
419 : count_offset = 8;
420 0 : else if (le16_to_cpu(dirent->rec_len) == 12) {
421 0 : dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
422 0 : if (le16_to_cpu(dp->rec_len) !=
423 0 : EXT4_BLOCK_SIZE(inode->i_sb) - 12)
424 : return NULL;
425 0 : root = (struct dx_root_info *)(((void *)dp + 12));
426 0 : if (root->reserved_zero ||
427 0 : root->info_length != sizeof(struct dx_root_info))
428 : return NULL;
429 : count_offset = 32;
430 : } else
431 : return NULL;
432 :
433 0 : if (offset)
434 0 : *offset = count_offset;
435 0 : return (struct dx_countlimit *)(((void *)dirent) + count_offset);
436 : }
437 :
438 0 : static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
439 : int count_offset, int count, struct dx_tail *t)
440 : {
441 0 : struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
442 0 : struct ext4_inode_info *ei = EXT4_I(inode);
443 0 : __u32 csum;
444 0 : int size;
445 0 : __u32 dummy_csum = 0;
446 0 : int offset = offsetof(struct dx_tail, dt_checksum);
447 :
448 0 : size = count_offset + (count * sizeof(struct dx_entry));
449 0 : csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
450 0 : csum = ext4_chksum(sbi, csum, (__u8 *)t, offset);
451 0 : csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
452 :
453 0 : return cpu_to_le32(csum);
454 : }
455 :
456 0 : static int ext4_dx_csum_verify(struct inode *inode,
457 : struct ext4_dir_entry *dirent)
458 : {
459 0 : struct dx_countlimit *c;
460 0 : struct dx_tail *t;
461 0 : int count_offset, limit, count;
462 :
463 0 : if (!ext4_has_metadata_csum(inode->i_sb))
464 : return 1;
465 :
466 0 : c = get_dx_countlimit(inode, dirent, &count_offset);
467 0 : if (!c) {
468 0 : EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
469 0 : return 0;
470 : }
471 0 : limit = le16_to_cpu(c->limit);
472 0 : count = le16_to_cpu(c->count);
473 0 : if (count_offset + (limit * sizeof(struct dx_entry)) >
474 0 : EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
475 0 : warn_no_space_for_csum(inode);
476 0 : return 0;
477 : }
478 0 : t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
479 :
480 0 : if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
481 : count, t))
482 0 : return 0;
483 : return 1;
484 : }
485 :
486 0 : static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
487 : {
488 0 : struct dx_countlimit *c;
489 0 : struct dx_tail *t;
490 0 : int count_offset, limit, count;
491 :
492 0 : if (!ext4_has_metadata_csum(inode->i_sb))
493 0 : return;
494 :
495 0 : c = get_dx_countlimit(inode, dirent, &count_offset);
496 0 : if (!c) {
497 0 : EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
498 0 : return;
499 : }
500 0 : limit = le16_to_cpu(c->limit);
501 0 : count = le16_to_cpu(c->count);
502 0 : if (count_offset + (limit * sizeof(struct dx_entry)) >
503 0 : EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
504 0 : warn_no_space_for_csum(inode);
505 0 : return;
506 : }
507 0 : t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
508 :
509 0 : t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
510 : }
511 :
512 0 : static inline int ext4_handle_dirty_dx_node(handle_t *handle,
513 : struct inode *inode,
514 : struct buffer_head *bh)
515 : {
516 0 : ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
517 0 : return ext4_handle_dirty_metadata(handle, inode, bh);
518 : }
519 :
520 : /*
521 : * p is at least 6 bytes before the end of page
522 : */
523 : static inline struct ext4_dir_entry_2 *
524 12964 : ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
525 : {
526 12964 : return (struct ext4_dir_entry_2 *)((char *)p +
527 12964 : ext4_rec_len_from_disk(p->rec_len, blocksize));
528 : }
529 :
530 : /*
531 : * Future: use high four bits of block for coalesce-on-delete flags
532 : * Mask them off for now.
533 : */
534 :
535 3345 : static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
536 : {
537 3345 : return le32_to_cpu(entry->block) & 0x0fffffff;
538 : }
539 :
540 0 : static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
541 : {
542 0 : entry->block = cpu_to_le32(value);
543 : }
544 :
545 10748 : static inline unsigned dx_get_hash(struct dx_entry *entry)
546 : {
547 10748 : return le32_to_cpu(entry->hash);
548 : }
549 :
550 0 : static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
551 : {
552 0 : entry->hash = cpu_to_le32(value);
553 : }
554 :
555 3809 : static inline unsigned dx_get_count(struct dx_entry *entries)
556 : {
557 3809 : return le16_to_cpu(((struct dx_countlimit *) entries)->count);
558 : }
559 :
560 6650 : static inline unsigned dx_get_limit(struct dx_entry *entries)
561 : {
562 6650 : return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
563 : }
564 :
565 0 : static inline void dx_set_count(struct dx_entry *entries, unsigned value)
566 : {
567 0 : ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
568 : }
569 :
570 0 : static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
571 : {
572 0 : ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
573 : }
574 :
575 3325 : static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
576 : {
577 3325 : unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
578 3325 : EXT4_DIR_REC_LEN(2) - infosize;
579 :
580 3325 : if (ext4_has_metadata_csum(dir->i_sb))
581 0 : entry_space -= sizeof(struct dx_tail);
582 3325 : return entry_space / sizeof(struct dx_entry);
583 : }
584 :
585 0 : static inline unsigned dx_node_limit(struct inode *dir)
586 : {
587 0 : unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
588 :
589 0 : if (ext4_has_metadata_csum(dir->i_sb))
590 0 : entry_space -= sizeof(struct dx_tail);
591 0 : return entry_space / sizeof(struct dx_entry);
592 : }
593 :
594 : /*
595 : * Debug
596 : */
597 : #ifdef DX_DEBUG
598 : static void dx_show_index(char * label, struct dx_entry *entries)
599 : {
600 : int i, n = dx_get_count (entries);
601 : printk(KERN_DEBUG "%s index", label);
602 : for (i = 0; i < n; i++) {
603 : printk(KERN_CONT " %x->%lu",
604 : i ? dx_get_hash(entries + i) : 0,
605 : (unsigned long)dx_get_block(entries + i));
606 : }
607 : printk(KERN_CONT "\n");
608 : }
609 :
610 : struct stats
611 : {
612 : unsigned names;
613 : unsigned space;
614 : unsigned bcount;
615 : };
616 :
617 : static struct stats dx_show_leaf(struct inode *dir,
618 : struct dx_hash_info *hinfo,
619 : struct ext4_dir_entry_2 *de,
620 : int size, int show_names)
621 : {
622 : unsigned names = 0, space = 0;
623 : char *base = (char *) de;
624 : struct dx_hash_info h = *hinfo;
625 :
626 : printk("names: ");
627 : while ((char *) de < base + size)
628 : {
629 : if (de->inode)
630 : {
631 : if (show_names)
632 : {
633 : #ifdef CONFIG_FS_ENCRYPTION
634 : int len;
635 : char *name;
636 : struct fscrypt_str fname_crypto_str =
637 : FSTR_INIT(NULL, 0);
638 : int res = 0;
639 :
640 : name = de->name;
641 : len = de->name_len;
642 : if (!IS_ENCRYPTED(dir)) {
643 : /* Directory is not encrypted */
644 : ext4fs_dirhash(dir, de->name,
645 : de->name_len, &h);
646 : printk("%*.s:(U)%x.%u ", len,
647 : name, h.hash,
648 : (unsigned) ((char *) de
649 : - base));
650 : } else {
651 : struct fscrypt_str de_name =
652 : FSTR_INIT(name, len);
653 :
654 : /* Directory is encrypted */
655 : res = fscrypt_fname_alloc_buffer(
656 : len, &fname_crypto_str);
657 : if (res)
658 : printk(KERN_WARNING "Error "
659 : "allocating crypto "
660 : "buffer--skipping "
661 : "crypto\n");
662 : res = fscrypt_fname_disk_to_usr(dir,
663 : 0, 0, &de_name,
664 : &fname_crypto_str);
665 : if (res) {
666 : printk(KERN_WARNING "Error "
667 : "converting filename "
668 : "from disk to usr"
669 : "\n");
670 : name = "??";
671 : len = 2;
672 : } else {
673 : name = fname_crypto_str.name;
674 : len = fname_crypto_str.len;
675 : }
676 : ext4fs_dirhash(dir, de->name,
677 : de->name_len, &h);
678 : printk("%*.s:(E)%x.%u ", len, name,
679 : h.hash, (unsigned) ((char *) de
680 : - base));
681 : fscrypt_fname_free_buffer(
682 : &fname_crypto_str);
683 : }
684 : #else
685 : int len = de->name_len;
686 : char *name = de->name;
687 : ext4fs_dirhash(dir, de->name, de->name_len, &h);
688 : printk("%*.s:%x.%u ", len, name, h.hash,
689 : (unsigned) ((char *) de - base));
690 : #endif
691 : }
692 : space += EXT4_DIR_REC_LEN(de->name_len);
693 : names++;
694 : }
695 : de = ext4_next_entry(de, size);
696 : }
697 : printk(KERN_CONT "(%i)\n", names);
698 : return (struct stats) { names, space, 1 };
699 : }
700 :
701 : struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
702 : struct dx_entry *entries, int levels)
703 : {
704 : unsigned blocksize = dir->i_sb->s_blocksize;
705 : unsigned count = dx_get_count(entries), names = 0, space = 0, i;
706 : unsigned bcount = 0;
707 : struct buffer_head *bh;
708 : printk("%i indexed blocks...\n", count);
709 : for (i = 0; i < count; i++, entries++)
710 : {
711 : ext4_lblk_t block = dx_get_block(entries);
712 : ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
713 : u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
714 : struct stats stats;
715 : printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
716 : bh = ext4_bread(NULL,dir, block, 0);
717 : if (!bh || IS_ERR(bh))
718 : continue;
719 : stats = levels?
720 : dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
721 : dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)
722 : bh->b_data, blocksize, 0);
723 : names += stats.names;
724 : space += stats.space;
725 : bcount += stats.bcount;
726 : brelse(bh);
727 : }
728 : if (bcount)
729 : printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
730 : levels ? "" : " ", names, space/bcount,
731 : (space/bcount)*100/blocksize);
732 : return (struct stats) { names, space, bcount};
733 : }
734 :
735 : /*
736 : * Linear search cross check
737 : */
738 : static inline void htree_rep_invariant_check(struct dx_entry *at,
739 : struct dx_entry *target,
740 : u32 hash, unsigned int n)
741 : {
742 : while (n--) {
743 : dxtrace(printk(KERN_CONT ","));
744 : if (dx_get_hash(++at) > hash) {
745 : at--;
746 : break;
747 : }
748 : }
749 : ASSERT(at == target - 1);
750 : }
751 : #else /* DX_DEBUG */
752 3325 : static inline void htree_rep_invariant_check(struct dx_entry *at,
753 : struct dx_entry *target,
754 : u32 hash, unsigned int n)
755 : {
756 3325 : }
757 : #endif /* DX_DEBUG */
758 :
759 : /*
760 : * Probe for a directory leaf block to search.
761 : *
762 : * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
763 : * error in the directory index, and the caller should fall back to
764 : * searching the directory normally. The callers of dx_probe **MUST**
765 : * check for this error code, and make sure it never gets reflected
766 : * back to userspace.
767 : */
768 : static struct dx_frame *
769 3325 : dx_probe(struct ext4_filename *fname, struct inode *dir,
770 : struct dx_hash_info *hinfo, struct dx_frame *frame_in)
771 : {
772 3325 : unsigned count, indirect;
773 3325 : struct dx_entry *at, *entries, *p, *q, *m;
774 3325 : struct dx_root *root;
775 3325 : struct dx_frame *frame = frame_in;
776 3325 : struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);
777 3325 : u32 hash;
778 :
779 3325 : memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0]));
780 3325 : frame->bh = ext4_read_dirblock(dir, 0, INDEX);
781 3325 : if (IS_ERR(frame->bh))
782 : return (struct dx_frame *) frame->bh;
783 :
784 3325 : root = (struct dx_root *) frame->bh->b_data;
785 3325 : if (root->info.hash_version != DX_HASH_TEA &&
786 : root->info.hash_version != DX_HASH_HALF_MD4 &&
787 : root->info.hash_version != DX_HASH_LEGACY) {
788 0 : ext4_warning_inode(dir, "Unrecognised inode hash code %u",
789 : root->info.hash_version);
790 0 : goto fail;
791 : }
792 3325 : if (fname)
793 3228 : hinfo = &fname->hinfo;
794 3325 : hinfo->hash_version = root->info.hash_version;
795 3325 : if (hinfo->hash_version <= DX_HASH_TEA)
796 3325 : hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
797 3325 : hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
798 3325 : if (fname && fname_name(fname))
799 3228 : ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), hinfo);
800 3325 : hash = hinfo->hash;
801 :
802 3325 : if (root->info.unused_flags & 1) {
803 0 : ext4_warning_inode(dir, "Unimplemented hash flags: %#06x",
804 : root->info.unused_flags);
805 0 : goto fail;
806 : }
807 :
808 3325 : indirect = root->info.indirect_levels;
809 6650 : if (indirect >= ext4_dir_htree_level(dir->i_sb)) {
810 0 : ext4_warning(dir->i_sb,
811 : "Directory (ino: %lu) htree depth %#06x exceed"
812 : "supported value", dir->i_ino,
813 : ext4_dir_htree_level(dir->i_sb));
814 0 : if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) {
815 0 : ext4_warning(dir->i_sb, "Enable large directory "
816 : "feature to access it");
817 : }
818 0 : goto fail;
819 : }
820 :
821 3325 : entries = (struct dx_entry *)(((char *)&root->info) +
822 3325 : root->info.info_length);
823 :
824 3325 : if (dx_get_limit(entries) != dx_root_limit(dir,
825 : root->info.info_length)) {
826 0 : ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
827 : dx_get_limit(entries),
828 : dx_root_limit(dir, root->info.info_length));
829 0 : goto fail;
830 : }
831 :
832 3325 : dxtrace(printk("Look up %x", hash));
833 3325 : while (1) {
834 3325 : count = dx_get_count(entries);
835 3325 : if (!count || count > dx_get_limit(entries)) {
836 0 : ext4_warning_inode(dir,
837 : "dx entry: count %u beyond limit %u",
838 : count, dx_get_limit(entries));
839 0 : goto fail;
840 : }
841 :
842 3325 : p = entries + 1;
843 3325 : q = entries + count - 1;
844 13683 : while (p <= q) {
845 10358 : m = p + (q - p) / 2;
846 10358 : dxtrace(printk(KERN_CONT "."));
847 10358 : if (dx_get_hash(m) > hash)
848 4917 : q = m - 1;
849 : else
850 5441 : p = m + 1;
851 : }
852 :
853 3325 : htree_rep_invariant_check(entries, p, hash, count - 1);
854 :
855 3325 : at = p - 1;
856 : dxtrace(printk(KERN_CONT " %x->%u\n",
857 : at == entries ? 0 : dx_get_hash(at),
858 3325 : dx_get_block(at)));
859 3325 : frame->entries = entries;
860 3325 : frame->at = at;
861 3325 : if (!indirect--)
862 3325 : return frame;
863 0 : frame++;
864 0 : frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
865 0 : if (IS_ERR(frame->bh)) {
866 0 : ret_err = (struct dx_frame *) frame->bh;
867 0 : frame->bh = NULL;
868 0 : goto fail;
869 : }
870 0 : entries = ((struct dx_node *) frame->bh->b_data)->entries;
871 :
872 0 : if (dx_get_limit(entries) != dx_node_limit(dir)) {
873 0 : ext4_warning_inode(dir,
874 : "dx entry: limit %u != node limit %u",
875 : dx_get_limit(entries), dx_node_limit(dir));
876 0 : goto fail;
877 : }
878 : }
879 0 : fail:
880 0 : while (frame >= frame_in) {
881 0 : brelse(frame->bh);
882 0 : frame--;
883 : }
884 :
885 0 : if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
886 0 : ext4_warning_inode(dir,
887 : "Corrupt directory, running e2fsck is recommended");
888 : return ret_err;
889 : }
890 :
891 3325 : static void dx_release(struct dx_frame *frames)
892 : {
893 3325 : struct dx_root_info *info;
894 3325 : int i;
895 3325 : unsigned int indirect_levels;
896 :
897 3325 : if (frames[0].bh == NULL)
898 : return;
899 :
900 3325 : info = &((struct dx_root *)frames[0].bh->b_data)->info;
901 : /* save local copy, "info" may be freed after brelse() */
902 3325 : indirect_levels = info->indirect_levels;
903 6650 : for (i = 0; i <= indirect_levels; i++) {
904 3325 : if (frames[i].bh == NULL)
905 : break;
906 3325 : brelse(frames[i].bh);
907 3325 : frames[i].bh = NULL;
908 : }
909 : }
910 :
911 : /*
912 : * This function increments the frame pointer to search the next leaf
913 : * block, and reads in the necessary intervening nodes if the search
914 : * should be necessary. Whether or not the search is necessary is
915 : * controlled by the hash parameter. If the hash value is even, then
916 : * the search is only continued if the next block starts with that
917 : * hash value. This is used if we are searching for a specific file.
918 : *
919 : * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
920 : *
921 : * This function returns 1 if the caller should continue to search,
922 : * or 0 if it should not. If there is an error reading one of the
923 : * index blocks, it will a negative error code.
924 : *
925 : * If start_hash is non-null, it will be filled in with the starting
926 : * hash of the next page.
927 : */
928 484 : static int ext4_htree_next_block(struct inode *dir, __u32 hash,
929 : struct dx_frame *frame,
930 : struct dx_frame *frames,
931 : __u32 *start_hash)
932 : {
933 484 : struct dx_frame *p;
934 484 : struct buffer_head *bh;
935 484 : int num_frames = 0;
936 484 : __u32 bhash;
937 :
938 484 : p = frame;
939 : /*
940 : * Find the next leaf page by incrementing the frame pointer.
941 : * If we run out of entries in the interior node, loop around and
942 : * increment pointer in the parent node. When we break out of
943 : * this loop, num_frames indicates the number of interior
944 : * nodes need to be read.
945 : */
946 484 : while (1) {
947 484 : if (++(p->at) < p->entries + dx_get_count(p->entries))
948 : break;
949 94 : if (p == frames)
950 : return 0;
951 0 : num_frames++;
952 0 : p--;
953 : }
954 :
955 : /*
956 : * If the hash is 1, then continue only if the next page has a
957 : * continuation hash of any value. This is used for readdir
958 : * handling. Otherwise, check to see if the hash matches the
959 : * desired contiuation hash. If it doesn't, return since
960 : * there's no point to read in the successive index pages.
961 : */
962 390 : bhash = dx_get_hash(p->at);
963 390 : if (start_hash)
964 109 : *start_hash = bhash;
965 390 : if ((hash & 1) == 0) {
966 281 : if ((bhash & ~1) != hash)
967 : return 0;
968 : }
969 : /*
970 : * If the hash is HASH_NB_ALWAYS, we always go to the next
971 : * block so no check is necessary
972 : */
973 109 : while (num_frames--) {
974 0 : bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
975 0 : if (IS_ERR(bh))
976 0 : return PTR_ERR(bh);
977 0 : p++;
978 0 : brelse(p->bh);
979 0 : p->bh = bh;
980 0 : p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
981 : }
982 : return 1;
983 : }
984 :
985 :
986 : /*
987 : * This function fills a red-black tree with information from a
988 : * directory block. It returns the number directory entries loaded
989 : * into the tree. If there is an error it is returned in err.
990 : */
991 666 : static int htree_dirblock_to_tree(struct file *dir_file,
992 : struct inode *dir, ext4_lblk_t block,
993 : struct dx_hash_info *hinfo,
994 : __u32 start_hash, __u32 start_minor_hash)
995 : {
996 666 : struct buffer_head *bh;
997 666 : struct ext4_dir_entry_2 *de, *top;
998 666 : int err = 0, count = 0;
999 666 : struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;
1000 :
1001 : dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
1002 666 : (unsigned long)block));
1003 666 : bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
1004 666 : if (IS_ERR(bh))
1005 0 : return PTR_ERR(bh);
1006 :
1007 666 : de = (struct ext4_dir_entry_2 *) bh->b_data;
1008 666 : top = (struct ext4_dir_entry_2 *) ((char *) de +
1009 666 : dir->i_sb->s_blocksize -
1010 : EXT4_DIR_REC_LEN(0));
1011 : /* Check if the directory is encrypted */
1012 666 : if (IS_ENCRYPTED(dir)) {
1013 0 : err = fscrypt_prepare_readdir(dir);
1014 0 : if (err < 0) {
1015 0 : brelse(bh);
1016 0 : return err;
1017 : }
1018 : err = fscrypt_fname_alloc_buffer(EXT4_NAME_LEN,
1019 : &fname_crypto_str);
1020 : if (err < 0) {
1021 : brelse(bh);
1022 : return err;
1023 : }
1024 : }
1025 :
1026 7490 : for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
1027 6824 : if (ext4_check_dir_entry(dir, NULL, de, bh,
1028 : bh->b_data, bh->b_size,
1029 : (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
1030 : + ((char *)de - bh->b_data))) {
1031 : /* silently ignore the rest of the block */
1032 : break;
1033 : }
1034 6824 : ext4fs_dirhash(dir, de->name, de->name_len, hinfo);
1035 6824 : if ((hinfo->hash < start_hash) ||
1036 52 : ((hinfo->hash == start_hash) &&
1037 52 : (hinfo->minor_hash < start_minor_hash)))
1038 0 : continue;
1039 6824 : if (de->inode == 0)
1040 67 : continue;
1041 6757 : if (!IS_ENCRYPTED(dir)) {
1042 6757 : tmp_str.name = de->name;
1043 6757 : tmp_str.len = de->name_len;
1044 6757 : err = ext4_htree_store_dirent(dir_file,
1045 : hinfo->hash, hinfo->minor_hash, de,
1046 : &tmp_str);
1047 : } else {
1048 0 : int save_len = fname_crypto_str.len;
1049 0 : struct fscrypt_str de_name = FSTR_INIT(de->name,
1050 : de->name_len);
1051 :
1052 : /* Directory is encrypted */
1053 0 : err = fscrypt_fname_disk_to_usr(dir, hinfo->hash,
1054 : hinfo->minor_hash, &de_name,
1055 : &fname_crypto_str);
1056 0 : if (err) {
1057 0 : count = err;
1058 0 : goto errout;
1059 : }
1060 : err = ext4_htree_store_dirent(dir_file,
1061 : hinfo->hash, hinfo->minor_hash, de,
1062 : &fname_crypto_str);
1063 : fname_crypto_str.len = save_len;
1064 : }
1065 6757 : if (err != 0) {
1066 0 : count = err;
1067 0 : goto errout;
1068 : }
1069 6757 : count++;
1070 : }
1071 666 : errout:
1072 666 : brelse(bh);
1073 666 : fscrypt_fname_free_buffer(&fname_crypto_str);
1074 : return count;
1075 : }
1076 :
1077 :
1078 : /*
1079 : * This function fills a red-black tree with information from a
1080 : * directory. We start scanning the directory in hash order, starting
1081 : * at start_hash and start_minor_hash.
1082 : *
1083 : * This function returns the number of entries inserted into the tree,
1084 : * or a negative error code.
1085 : */
1086 646 : int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
1087 : __u32 start_minor_hash, __u32 *next_hash)
1088 : {
1089 646 : struct dx_hash_info hinfo;
1090 646 : struct ext4_dir_entry_2 *de;
1091 646 : struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1092 646 : struct inode *dir;
1093 646 : ext4_lblk_t block;
1094 646 : int count = 0;
1095 646 : int ret, err;
1096 646 : __u32 hashval;
1097 646 : struct fscrypt_str tmp_str;
1098 :
1099 : dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
1100 646 : start_hash, start_minor_hash));
1101 646 : dir = file_inode(dir_file);
1102 646 : if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
1103 549 : hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
1104 549 : if (hinfo.hash_version <= DX_HASH_TEA)
1105 549 : hinfo.hash_version +=
1106 549 : EXT4_SB(dir->i_sb)->s_hash_unsigned;
1107 549 : hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1108 549 : if (ext4_has_inline_data(dir)) {
1109 0 : int has_inline_data = 1;
1110 0 : count = ext4_inlinedir_to_tree(dir_file, dir, 0,
1111 : &hinfo, start_hash,
1112 : start_minor_hash,
1113 : &has_inline_data);
1114 0 : if (has_inline_data) {
1115 0 : *next_hash = ~0;
1116 0 : return count;
1117 : }
1118 : }
1119 549 : count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
1120 : start_hash, start_minor_hash);
1121 549 : *next_hash = ~0;
1122 549 : return count;
1123 : }
1124 97 : hinfo.hash = start_hash;
1125 97 : hinfo.minor_hash = 0;
1126 97 : frame = dx_probe(NULL, dir, &hinfo, frames);
1127 97 : if (IS_ERR(frame))
1128 0 : return PTR_ERR(frame);
1129 :
1130 : /* Add '.' and '..' from the htree header */
1131 97 : if (!start_hash && !start_minor_hash) {
1132 8 : de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1133 8 : tmp_str.name = de->name;
1134 8 : tmp_str.len = de->name_len;
1135 8 : err = ext4_htree_store_dirent(dir_file, 0, 0,
1136 : de, &tmp_str);
1137 8 : if (err != 0)
1138 0 : goto errout;
1139 : count++;
1140 : }
1141 97 : if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
1142 8 : de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
1143 8 : de = ext4_next_entry(de, dir->i_sb->s_blocksize);
1144 8 : tmp_str.name = de->name;
1145 8 : tmp_str.len = de->name_len;
1146 8 : err = ext4_htree_store_dirent(dir_file, 2, 0,
1147 : de, &tmp_str);
1148 8 : if (err != 0)
1149 0 : goto errout;
1150 8 : count++;
1151 : }
1152 :
1153 117 : while (1) {
1154 117 : if (fatal_signal_pending(current)) {
1155 0 : err = -ERESTARTSYS;
1156 0 : goto errout;
1157 : }
1158 117 : cond_resched();
1159 117 : block = dx_get_block(frame->at);
1160 117 : ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
1161 : start_hash, start_minor_hash);
1162 117 : if (ret < 0) {
1163 0 : err = ret;
1164 0 : goto errout;
1165 : }
1166 117 : count += ret;
1167 117 : hashval = ~0;
1168 117 : ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
1169 : frame, frames, &hashval);
1170 117 : *next_hash = hashval;
1171 117 : if (ret < 0) {
1172 0 : err = ret;
1173 0 : goto errout;
1174 : }
1175 : /*
1176 : * Stop if: (a) there are no more entries, or
1177 : * (b) we have inserted at least one entry and the
1178 : * next hash value is not a continuation
1179 : */
1180 117 : if ((ret == 0) ||
1181 89 : (count && ((hashval & 1) == 0)))
1182 : break;
1183 : }
1184 97 : dx_release(frames);
1185 : dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1186 97 : "next hash: %x\n", count, *next_hash));
1187 97 : return count;
1188 0 : errout:
1189 0 : dx_release(frames);
1190 0 : return (err);
1191 : }
1192 :
1193 7401 : static inline int search_dirblock(struct buffer_head *bh,
1194 : struct inode *dir,
1195 : struct ext4_filename *fname,
1196 : unsigned int offset,
1197 : struct ext4_dir_entry_2 **res_dir)
1198 : {
1199 7401 : return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,
1200 : fname, offset, res_dir);
1201 : }
1202 :
1203 : /*
1204 : * Directory block splitting, compacting
1205 : */
1206 :
1207 : /*
1208 : * Create map of hash values, offsets, and sizes, stored at end of block.
1209 : * Returns number of entries mapped.
1210 : */
1211 0 : static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de,
1212 : unsigned blocksize, struct dx_hash_info *hinfo,
1213 : struct dx_map_entry *map_tail)
1214 : {
1215 0 : int count = 0;
1216 0 : char *base = (char *) de;
1217 0 : struct dx_hash_info h = *hinfo;
1218 :
1219 0 : while ((char *) de < base + blocksize) {
1220 0 : if (de->name_len && de->inode) {
1221 0 : ext4fs_dirhash(dir, de->name, de->name_len, &h);
1222 0 : map_tail--;
1223 0 : map_tail->hash = h.hash;
1224 0 : map_tail->offs = ((char *) de - base)>>2;
1225 0 : map_tail->size = le16_to_cpu(de->rec_len);
1226 0 : count++;
1227 0 : cond_resched();
1228 : }
1229 : /* XXX: do we need to check rec_len == 0 case? -Chris */
1230 0 : de = ext4_next_entry(de, blocksize);
1231 : }
1232 0 : return count;
1233 : }
1234 :
1235 : /* Sort map by hash value */
1236 0 : static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1237 : {
1238 0 : struct dx_map_entry *p, *q, *top = map + count - 1;
1239 0 : int more;
1240 : /* Combsort until bubble sort doesn't suck */
1241 0 : while (count > 2) {
1242 0 : count = count*10/13;
1243 0 : if (count - 9 < 2) /* 9, 10 -> 11 */
1244 0 : count = 11;
1245 0 : for (p = top, q = p - count; q >= map; p--, q--)
1246 0 : if (p->hash < q->hash)
1247 0 : swap(*p, *q);
1248 : }
1249 : /* Garden variety bubble sort */
1250 0 : do {
1251 0 : more = 0;
1252 0 : q = top;
1253 0 : while (q-- > map) {
1254 0 : if (q[1].hash >= q[0].hash)
1255 0 : continue;
1256 0 : swap(*(q+1), *q);
1257 0 : more = 1;
1258 : }
1259 0 : } while(more);
1260 0 : }
1261 :
1262 0 : static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
1263 : {
1264 0 : struct dx_entry *entries = frame->entries;
1265 0 : struct dx_entry *old = frame->at, *new = old + 1;
1266 0 : int count = dx_get_count(entries);
1267 :
1268 0 : ASSERT(count < dx_get_limit(entries));
1269 0 : ASSERT(old < entries + count);
1270 0 : memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1271 0 : dx_set_hash(new, hash);
1272 0 : dx_set_block(new, block);
1273 0 : dx_set_count(entries, count + 1);
1274 0 : }
1275 :
1276 : #ifdef CONFIG_UNICODE
1277 : /*
1278 : * Test whether a case-insensitive directory entry matches the filename
1279 : * being searched for. If quick is set, assume the name being looked up
1280 : * is already in the casefolded form.
1281 : *
1282 : * Returns: 0 if the directory entry matches, more than 0 if it
1283 : * doesn't match or less than zero on error.
1284 : */
1285 : int ext4_ci_compare(const struct inode *parent, const struct qstr *name,
1286 : const struct qstr *entry, bool quick)
1287 : {
1288 : const struct super_block *sb = parent->i_sb;
1289 : const struct unicode_map *um = sb->s_encoding;
1290 : int ret;
1291 :
1292 : if (quick)
1293 : ret = utf8_strncasecmp_folded(um, name, entry);
1294 : else
1295 : ret = utf8_strncasecmp(um, name, entry);
1296 :
1297 : if (ret < 0) {
1298 : /* Handle invalid character sequence as either an error
1299 : * or as an opaque byte sequence.
1300 : */
1301 : if (sb_has_strict_encoding(sb))
1302 : return -EINVAL;
1303 :
1304 : if (name->len != entry->len)
1305 : return 1;
1306 :
1307 : return !!memcmp(name->name, entry->name, name->len);
1308 : }
1309 :
1310 : return ret;
1311 : }
1312 :
1313 : void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
1314 : struct fscrypt_str *cf_name)
1315 : {
1316 : int len;
1317 :
1318 : if (!IS_CASEFOLDED(dir) || !dir->i_sb->s_encoding) {
1319 : cf_name->name = NULL;
1320 : return;
1321 : }
1322 :
1323 : cf_name->name = kmalloc(EXT4_NAME_LEN, GFP_NOFS);
1324 : if (!cf_name->name)
1325 : return;
1326 :
1327 : len = utf8_casefold(dir->i_sb->s_encoding,
1328 : iname, cf_name->name,
1329 : EXT4_NAME_LEN);
1330 : if (len <= 0) {
1331 : kfree(cf_name->name);
1332 : cf_name->name = NULL;
1333 : return;
1334 : }
1335 : cf_name->len = (unsigned) len;
1336 :
1337 : }
1338 : #endif
1339 :
1340 : /*
1341 : * Test whether a directory entry matches the filename being searched for.
1342 : *
1343 : * Return: %true if the directory entry matches, otherwise %false.
1344 : */
1345 246325 : static inline bool ext4_match(const struct inode *parent,
1346 : const struct ext4_filename *fname,
1347 : const struct ext4_dir_entry_2 *de)
1348 : {
1349 246325 : struct fscrypt_name f;
1350 : #ifdef CONFIG_UNICODE
1351 : const struct qstr entry = {.name = de->name, .len = de->name_len};
1352 : #endif
1353 :
1354 246325 : if (!de->inode)
1355 : return false;
1356 :
1357 246046 : f.usr_fname = fname->usr_fname;
1358 246046 : f.disk_name = fname->disk_name;
1359 : #ifdef CONFIG_FS_ENCRYPTION
1360 : f.crypto_buf = fname->crypto_buf;
1361 : #endif
1362 :
1363 : #ifdef CONFIG_UNICODE
1364 : if (parent->i_sb->s_encoding && IS_CASEFOLDED(parent)) {
1365 : if (fname->cf_name.name) {
1366 : struct qstr cf = {.name = fname->cf_name.name,
1367 : .len = fname->cf_name.len};
1368 : return !ext4_ci_compare(parent, &cf, &entry, true);
1369 : }
1370 : return !ext4_ci_compare(parent, fname->usr_fname, &entry,
1371 : false);
1372 : }
1373 : #endif
1374 :
1375 246046 : return fscrypt_match_name(&f, de->name, de->name_len);
1376 : }
1377 :
1378 : /*
1379 : * Returns 0 if not found, -1 on failure, and 1 on success
1380 : */
1381 7401 : int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,
1382 : struct inode *dir, struct ext4_filename *fname,
1383 : unsigned int offset, struct ext4_dir_entry_2 **res_dir)
1384 : {
1385 7401 : struct ext4_dir_entry_2 * de;
1386 7401 : char * dlimit;
1387 7401 : int de_len;
1388 :
1389 7401 : de = (struct ext4_dir_entry_2 *)search_buf;
1390 7401 : dlimit = search_buf + buf_size;
1391 234013 : while ((char *) de < dlimit) {
1392 : /* this code is executed quadratically often */
1393 : /* do minimal checking `by hand' */
1394 231923 : if ((char *) de + de->name_len <= dlimit &&
1395 231922 : ext4_match(dir, fname, de)) {
1396 : /* found a match - just to be sure, do
1397 : * a full check */
1398 5311 : if (ext4_check_dir_entry(dir, NULL, de, bh, search_buf,
1399 : buf_size, offset))
1400 : return -1;
1401 5311 : *res_dir = de;
1402 5311 : return 1;
1403 : }
1404 : /* prevent looping on a bad block */
1405 226612 : de_len = ext4_rec_len_from_disk(de->rec_len,
1406 226612 : dir->i_sb->s_blocksize);
1407 226612 : if (de_len <= 0)
1408 : return -1;
1409 226612 : offset += de_len;
1410 226612 : de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
1411 : }
1412 : return 0;
1413 : }
1414 :
1415 298 : static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1416 : struct ext4_dir_entry *de)
1417 : {
1418 298 : struct super_block *sb = dir->i_sb;
1419 :
1420 596 : if (!is_dx(dir))
1421 298 : return 0;
1422 0 : if (block == 0)
1423 : return 1;
1424 0 : if (de->inode == 0 &&
1425 0 : ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
1426 : sb->s_blocksize)
1427 0 : return 1;
1428 : return 0;
1429 : }
1430 :
1431 : /*
1432 : * __ext4_find_entry()
1433 : *
1434 : * finds an entry in the specified directory with the wanted name. It
1435 : * returns the cache buffer in which the entry was found, and the entry
1436 : * itself (as a parameter - res_dir). It does NOT read the inode of the
1437 : * entry - you'll have to do that yourself if you want to.
1438 : *
1439 : * The returned buffer_head has ->b_count elevated. The caller is expected
1440 : * to brelse() it when appropriate.
1441 : */
1442 7401 : static struct buffer_head *__ext4_find_entry(struct inode *dir,
1443 : struct ext4_filename *fname,
1444 : struct ext4_dir_entry_2 **res_dir,
1445 : int *inlined)
1446 : {
1447 7401 : struct super_block *sb;
1448 7401 : struct buffer_head *bh_use[NAMEI_RA_SIZE];
1449 7401 : struct buffer_head *bh, *ret = NULL;
1450 7401 : ext4_lblk_t start, block;
1451 7401 : const u8 *name = fname->usr_fname->name;
1452 7401 : size_t ra_max = 0; /* Number of bh's in the readahead
1453 : buffer, bh_use[] */
1454 7401 : size_t ra_ptr = 0; /* Current index into readahead
1455 : buffer */
1456 7401 : ext4_lblk_t nblocks;
1457 7401 : int i, namelen, retval;
1458 :
1459 7401 : *res_dir = NULL;
1460 7401 : sb = dir->i_sb;
1461 7401 : namelen = fname->usr_fname->len;
1462 7401 : if (namelen > EXT4_NAME_LEN)
1463 : return NULL;
1464 :
1465 7401 : if (ext4_has_inline_data(dir)) {
1466 0 : int has_inline_data = 1;
1467 0 : ret = ext4_find_inline_entry(dir, fname, res_dir,
1468 : &has_inline_data);
1469 0 : if (has_inline_data) {
1470 0 : if (inlined)
1471 0 : *inlined = 1;
1472 0 : goto cleanup_and_exit;
1473 : }
1474 : }
1475 :
1476 7401 : if ((namelen <= 2) && (name[0] == '.') &&
1477 0 : (name[1] == '.' || name[1] == '\0')) {
1478 : /*
1479 : * "." or ".." will only be in the first block
1480 : * NFS may look up ".."; "." should be handled by the VFS
1481 : */
1482 0 : block = start = 0;
1483 0 : nblocks = 1;
1484 0 : goto restart;
1485 : }
1486 14802 : if (is_dx(dir)) {
1487 3224 : ret = ext4_dx_find_entry(dir, fname, res_dir);
1488 : /*
1489 : * On success, or if the error was file not found,
1490 : * return. Otherwise, fall back to doing a search the
1491 : * old fashioned way.
1492 : */
1493 3224 : if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR)
1494 3224 : goto cleanup_and_exit;
1495 : dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1496 : "falling back\n"));
1497 : ret = NULL;
1498 : }
1499 4177 : nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1500 4177 : if (!nblocks) {
1501 0 : ret = NULL;
1502 0 : goto cleanup_and_exit;
1503 : }
1504 4177 : start = EXT4_I(dir)->i_dir_start_lookup;
1505 4177 : if (start >= nblocks)
1506 0 : start = 0;
1507 4177 : block = start;
1508 4177 : restart:
1509 4177 : do {
1510 : /*
1511 : * We deal with the read-ahead logic here.
1512 : */
1513 4177 : cond_resched();
1514 4177 : if (ra_ptr >= ra_max) {
1515 : /* Refill the readahead buffer */
1516 4177 : ra_ptr = 0;
1517 4177 : if (block < start)
1518 0 : ra_max = start - block;
1519 : else
1520 4177 : ra_max = nblocks - block;
1521 4177 : ra_max = min(ra_max, ARRAY_SIZE(bh_use));
1522 4177 : retval = ext4_bread_batch(dir, block, ra_max,
1523 : false /* wait */, bh_use);
1524 4177 : if (retval) {
1525 0 : ret = ERR_PTR(retval);
1526 0 : ra_max = 0;
1527 0 : goto cleanup_and_exit;
1528 : }
1529 : }
1530 4177 : if ((bh = bh_use[ra_ptr++]) == NULL)
1531 0 : goto next;
1532 4177 : wait_on_buffer(bh);
1533 4177 : if (!buffer_uptodate(bh)) {
1534 0 : EXT4_ERROR_INODE_ERR(dir, EIO,
1535 : "reading directory lblock %lu",
1536 : (unsigned long) block);
1537 0 : brelse(bh);
1538 0 : ret = ERR_PTR(-EIO);
1539 0 : goto cleanup_and_exit;
1540 : }
1541 4475 : if (!buffer_verified(bh) &&
1542 298 : !is_dx_internal_node(dir, block,
1543 596 : (struct ext4_dir_entry *)bh->b_data) &&
1544 298 : !ext4_dirblock_csum_verify(dir, bh)) {
1545 0 : EXT4_ERROR_INODE_ERR(dir, EFSBADCRC,
1546 : "checksumming directory "
1547 : "block %lu", (unsigned long)block);
1548 0 : brelse(bh);
1549 0 : ret = ERR_PTR(-EFSBADCRC);
1550 0 : goto cleanup_and_exit;
1551 : }
1552 4177 : set_buffer_verified(bh);
1553 8354 : i = search_dirblock(bh, dir, fname,
1554 4177 : block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
1555 4177 : if (i == 1) {
1556 2454 : EXT4_I(dir)->i_dir_start_lookup = block;
1557 2454 : ret = bh;
1558 2454 : goto cleanup_and_exit;
1559 : } else {
1560 1723 : brelse(bh);
1561 1723 : if (i < 0)
1562 0 : goto cleanup_and_exit;
1563 : }
1564 1723 : next:
1565 1723 : if (++block >= nblocks)
1566 1723 : block = 0;
1567 1723 : } while (block != start);
1568 :
1569 : /*
1570 : * If the directory has grown while we were searching, then
1571 : * search the last part of the directory before giving up.
1572 : */
1573 1723 : block = nblocks;
1574 1723 : nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1575 1723 : if (block < nblocks) {
1576 0 : start = 0;
1577 0 : goto restart;
1578 : }
1579 :
1580 7401 : cleanup_and_exit:
1581 : /* Clean up the read-ahead blocks */
1582 7401 : for (; ra_ptr < ra_max; ra_ptr++)
1583 0 : brelse(bh_use[ra_ptr]);
1584 : return ret;
1585 : }
1586 :
1587 365 : static struct buffer_head *ext4_find_entry(struct inode *dir,
1588 : const struct qstr *d_name,
1589 : struct ext4_dir_entry_2 **res_dir,
1590 : int *inlined)
1591 : {
1592 365 : int err;
1593 365 : struct ext4_filename fname;
1594 365 : struct buffer_head *bh;
1595 :
1596 365 : err = ext4_fname_setup_filename(dir, d_name, 1, &fname);
1597 365 : if (err == -ENOENT)
1598 : return NULL;
1599 365 : if (err)
1600 : return ERR_PTR(err);
1601 :
1602 365 : bh = __ext4_find_entry(dir, &fname, res_dir, inlined);
1603 :
1604 365 : ext4_fname_free_filename(&fname);
1605 365 : return bh;
1606 : }
1607 :
1608 7036 : static struct buffer_head *ext4_lookup_entry(struct inode *dir,
1609 : struct dentry *dentry,
1610 : struct ext4_dir_entry_2 **res_dir)
1611 : {
1612 7036 : int err;
1613 7036 : struct ext4_filename fname;
1614 7036 : struct buffer_head *bh;
1615 :
1616 7036 : err = ext4_fname_prepare_lookup(dir, dentry, &fname);
1617 7036 : generic_set_encrypted_ci_d_ops(dentry);
1618 7036 : if (err == -ENOENT)
1619 : return NULL;
1620 7036 : if (err)
1621 : return ERR_PTR(err);
1622 :
1623 7036 : bh = __ext4_find_entry(dir, &fname, res_dir, NULL);
1624 :
1625 7036 : ext4_fname_free_filename(&fname);
1626 7036 : return bh;
1627 : }
1628 :
1629 3224 : static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
1630 : struct ext4_filename *fname,
1631 : struct ext4_dir_entry_2 **res_dir)
1632 : {
1633 3224 : struct super_block * sb = dir->i_sb;
1634 3224 : struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
1635 3224 : struct buffer_head *bh;
1636 3224 : ext4_lblk_t block;
1637 3224 : int retval;
1638 :
1639 : #ifdef CONFIG_FS_ENCRYPTION
1640 : *res_dir = NULL;
1641 : #endif
1642 3224 : frame = dx_probe(fname, dir, NULL, frames);
1643 3224 : if (IS_ERR(frame))
1644 : return (struct buffer_head *) frame;
1645 3224 : do {
1646 3224 : block = dx_get_block(frame->at);
1647 3224 : bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);
1648 3224 : if (IS_ERR(bh))
1649 0 : goto errout;
1650 :
1651 6448 : retval = search_dirblock(bh, dir, fname,
1652 3224 : block << EXT4_BLOCK_SIZE_BITS(sb),
1653 : res_dir);
1654 3224 : if (retval == 1)
1655 2857 : goto success;
1656 367 : brelse(bh);
1657 367 : if (retval == -1) {
1658 0 : bh = ERR_PTR(ERR_BAD_DX_DIR);
1659 0 : goto errout;
1660 : }
1661 :
1662 : /* Check to see if we should continue to search */
1663 367 : retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame,
1664 : frames, NULL);
1665 367 : if (retval < 0) {
1666 0 : ext4_warning_inode(dir,
1667 : "error %d reading directory index block",
1668 : retval);
1669 0 : bh = ERR_PTR(retval);
1670 0 : goto errout;
1671 : }
1672 367 : } while (retval == 1);
1673 :
1674 : bh = NULL;
1675 3224 : errout:
1676 3224 : dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name));
1677 3224 : success:
1678 3224 : dx_release(frames);
1679 3224 : return bh;
1680 : }
1681 :
1682 7036 : static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
1683 : {
1684 7036 : struct inode *inode;
1685 7036 : struct ext4_dir_entry_2 *de;
1686 7036 : struct buffer_head *bh;
1687 :
1688 7036 : if (dentry->d_name.len > EXT4_NAME_LEN)
1689 7036 : return ERR_PTR(-ENAMETOOLONG);
1690 :
1691 7036 : bh = ext4_lookup_entry(dir, dentry, &de);
1692 7036 : if (IS_ERR(bh))
1693 7036 : return ERR_CAST(bh);
1694 7036 : inode = NULL;
1695 7036 : if (bh) {
1696 5017 : __u32 ino = le32_to_cpu(de->inode);
1697 5017 : brelse(bh);
1698 5017 : if (!ext4_valid_inum(dir->i_sb, ino)) {
1699 0 : EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1700 0 : return ERR_PTR(-EFSCORRUPTED);
1701 : }
1702 5017 : if (unlikely(ino == dir->i_ino)) {
1703 0 : EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
1704 : dentry);
1705 0 : return ERR_PTR(-EFSCORRUPTED);
1706 : }
1707 5017 : inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL);
1708 5017 : if (inode == ERR_PTR(-ESTALE)) {
1709 0 : EXT4_ERROR_INODE(dir,
1710 : "deleted inode referenced: %u",
1711 : ino);
1712 0 : return ERR_PTR(-EFSCORRUPTED);
1713 : }
1714 5017 : if (!IS_ERR(inode) && IS_ENCRYPTED(dir) &&
1715 0 : (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
1716 0 : !fscrypt_has_permitted_context(dir, inode)) {
1717 0 : ext4_warning(inode->i_sb,
1718 : "Inconsistent encryption contexts: %lu/%lu",
1719 : dir->i_ino, inode->i_ino);
1720 0 : iput(inode);
1721 0 : return ERR_PTR(-EPERM);
1722 : }
1723 : }
1724 :
1725 : #ifdef CONFIG_UNICODE
1726 : if (!inode && IS_CASEFOLDED(dir)) {
1727 : /* Eventually we want to call d_add_ci(dentry, NULL)
1728 : * for negative dentries in the encoding case as
1729 : * well. For now, prevent the negative dentry
1730 : * from being cached.
1731 : */
1732 : return NULL;
1733 : }
1734 : #endif
1735 7036 : return d_splice_alias(inode, dentry);
1736 : }
1737 :
1738 :
1739 0 : struct dentry *ext4_get_parent(struct dentry *child)
1740 : {
1741 0 : __u32 ino;
1742 0 : static const struct qstr dotdot = QSTR_INIT("..", 2);
1743 0 : struct ext4_dir_entry_2 * de;
1744 0 : struct buffer_head *bh;
1745 :
1746 0 : bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL);
1747 0 : if (IS_ERR(bh))
1748 0 : return ERR_CAST(bh);
1749 0 : if (!bh)
1750 0 : return ERR_PTR(-ENOENT);
1751 0 : ino = le32_to_cpu(de->inode);
1752 0 : brelse(bh);
1753 :
1754 0 : if (!ext4_valid_inum(child->d_sb, ino)) {
1755 0 : EXT4_ERROR_INODE(d_inode(child),
1756 : "bad parent inode number: %u", ino);
1757 0 : return ERR_PTR(-EFSCORRUPTED);
1758 : }
1759 :
1760 0 : return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL));
1761 : }
1762 :
1763 : /*
1764 : * Move count entries from end of map between two memory locations.
1765 : * Returns pointer to last entry moved.
1766 : */
1767 : static struct ext4_dir_entry_2 *
1768 0 : dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1769 : unsigned blocksize)
1770 : {
1771 0 : unsigned rec_len = 0;
1772 :
1773 0 : while (count--) {
1774 0 : struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
1775 0 : (from + (map->offs<<2));
1776 0 : rec_len = EXT4_DIR_REC_LEN(de->name_len);
1777 0 : memcpy (to, de, rec_len);
1778 0 : ((struct ext4_dir_entry_2 *) to)->rec_len =
1779 0 : ext4_rec_len_to_disk(rec_len, blocksize);
1780 0 : de->inode = 0;
1781 0 : map++;
1782 0 : to += rec_len;
1783 : }
1784 0 : return (struct ext4_dir_entry_2 *) (to - rec_len);
1785 : }
1786 :
1787 : /*
1788 : * Compact each dir entry in the range to the minimal rec_len.
1789 : * Returns pointer to last entry in range.
1790 : */
1791 0 : static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
1792 : {
1793 0 : struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
1794 0 : unsigned rec_len = 0;
1795 :
1796 0 : prev = to = de;
1797 0 : while ((char*)de < base + blocksize) {
1798 0 : next = ext4_next_entry(de, blocksize);
1799 0 : if (de->inode && de->name_len) {
1800 0 : rec_len = EXT4_DIR_REC_LEN(de->name_len);
1801 0 : if (de > to)
1802 0 : memmove(to, de, rec_len);
1803 0 : to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
1804 0 : prev = to;
1805 0 : to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
1806 : }
1807 : de = next;
1808 : }
1809 0 : return prev;
1810 : }
1811 :
1812 : /*
1813 : * Split a full leaf block to make room for a new dir entry.
1814 : * Allocate a new block, and move entries so that they are approx. equally full.
1815 : * Returns pointer to de in block into which the new entry will be inserted.
1816 : */
1817 0 : static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1818 : struct buffer_head **bh,struct dx_frame *frame,
1819 : struct dx_hash_info *hinfo)
1820 : {
1821 0 : unsigned blocksize = dir->i_sb->s_blocksize;
1822 0 : unsigned count, continued;
1823 0 : struct buffer_head *bh2;
1824 0 : ext4_lblk_t newblock;
1825 0 : u32 hash2;
1826 0 : struct dx_map_entry *map;
1827 0 : char *data1 = (*bh)->b_data, *data2;
1828 0 : unsigned split, move, size;
1829 0 : struct ext4_dir_entry_2 *de = NULL, *de2;
1830 0 : int csum_size = 0;
1831 0 : int err = 0, i;
1832 :
1833 0 : if (ext4_has_metadata_csum(dir->i_sb))
1834 0 : csum_size = sizeof(struct ext4_dir_entry_tail);
1835 :
1836 0 : bh2 = ext4_append(handle, dir, &newblock);
1837 0 : if (IS_ERR(bh2)) {
1838 0 : brelse(*bh);
1839 0 : *bh = NULL;
1840 0 : return (struct ext4_dir_entry_2 *) bh2;
1841 : }
1842 :
1843 0 : BUFFER_TRACE(*bh, "get_write_access");
1844 0 : err = ext4_journal_get_write_access(handle, *bh);
1845 0 : if (err)
1846 0 : goto journal_error;
1847 :
1848 0 : BUFFER_TRACE(frame->bh, "get_write_access");
1849 0 : err = ext4_journal_get_write_access(handle, frame->bh);
1850 0 : if (err)
1851 0 : goto journal_error;
1852 :
1853 0 : data2 = bh2->b_data;
1854 :
1855 : /* create map in the end of data2 block */
1856 0 : map = (struct dx_map_entry *) (data2 + blocksize);
1857 0 : count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1,
1858 : blocksize, hinfo, map);
1859 0 : map -= count;
1860 0 : dx_sort_map(map, count);
1861 : /* Ensure that neither split block is over half full */
1862 0 : size = 0;
1863 0 : move = 0;
1864 0 : for (i = count-1; i >= 0; i--) {
1865 : /* is more than half of this entry in 2nd half of the block? */
1866 0 : if (size + map[i].size/2 > blocksize/2)
1867 : break;
1868 0 : size += map[i].size;
1869 0 : move++;
1870 : }
1871 : /*
1872 : * map index at which we will split
1873 : *
1874 : * If the sum of active entries didn't exceed half the block size, just
1875 : * split it in half by count; each resulting block will have at least
1876 : * half the space free.
1877 : */
1878 0 : if (i > 0)
1879 0 : split = count - move;
1880 : else
1881 0 : split = count/2;
1882 :
1883 0 : hash2 = map[split].hash;
1884 0 : continued = hash2 == map[split - 1].hash;
1885 : dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1886 : (unsigned long)dx_get_block(frame->at),
1887 0 : hash2, split, count-split));
1888 :
1889 : /* Fancy dance to stay within two buffers */
1890 0 : de2 = dx_move_dirents(data1, data2, map + split, count - split,
1891 : blocksize);
1892 0 : de = dx_pack_dirents(data1, blocksize);
1893 0 : de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1894 : (char *) de,
1895 : blocksize);
1896 0 : de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1897 : (char *) de2,
1898 : blocksize);
1899 0 : if (csum_size) {
1900 0 : ext4_initialize_dirent_tail(*bh, blocksize);
1901 0 : ext4_initialize_dirent_tail(bh2, blocksize);
1902 : }
1903 :
1904 : dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,
1905 0 : blocksize, 1));
1906 : dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,
1907 0 : blocksize, 1));
1908 :
1909 : /* Which block gets the new entry? */
1910 0 : if (hinfo->hash >= hash2) {
1911 0 : swap(*bh, bh2);
1912 0 : de = de2;
1913 : }
1914 0 : dx_insert_block(frame, hash2 + continued, newblock);
1915 0 : err = ext4_handle_dirty_dirblock(handle, dir, bh2);
1916 0 : if (err)
1917 0 : goto journal_error;
1918 0 : err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
1919 0 : if (err)
1920 0 : goto journal_error;
1921 0 : brelse(bh2);
1922 : dxtrace(dx_show_index("frame", frame->entries));
1923 : return de;
1924 :
1925 0 : journal_error:
1926 0 : brelse(*bh);
1927 0 : brelse(bh2);
1928 0 : *bh = NULL;
1929 0 : ext4_std_error(dir->i_sb, err);
1930 0 : return ERR_PTR(err);
1931 : }
1932 :
1933 708 : int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1934 : struct buffer_head *bh,
1935 : void *buf, int buf_size,
1936 : struct ext4_filename *fname,
1937 : struct ext4_dir_entry_2 **dest_de)
1938 : {
1939 708 : struct ext4_dir_entry_2 *de;
1940 708 : unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname));
1941 708 : int nlen, rlen;
1942 708 : unsigned int offset = 0;
1943 708 : char *top;
1944 :
1945 708 : de = (struct ext4_dir_entry_2 *)buf;
1946 708 : top = buf + buf_size - reclen;
1947 14401 : while ((char *) de <= top) {
1948 14401 : if (ext4_check_dir_entry(dir, NULL, de, bh,
1949 : buf, buf_size, offset))
1950 : return -EFSCORRUPTED;
1951 14401 : if (ext4_match(dir, fname, de))
1952 : return -EEXIST;
1953 14401 : nlen = EXT4_DIR_REC_LEN(de->name_len);
1954 14401 : rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1955 14401 : if ((de->inode ? rlen - nlen : rlen) >= reclen)
1956 : break;
1957 13693 : de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1958 13693 : offset += rlen;
1959 : }
1960 708 : if ((char *) de > top)
1961 : return -ENOSPC;
1962 :
1963 708 : *dest_de = de;
1964 708 : return 0;
1965 : }
1966 :
1967 708 : void ext4_insert_dentry(struct inode *inode,
1968 : struct ext4_dir_entry_2 *de,
1969 : int buf_size,
1970 : struct ext4_filename *fname)
1971 : {
1972 :
1973 708 : int nlen, rlen;
1974 :
1975 708 : nlen = EXT4_DIR_REC_LEN(de->name_len);
1976 708 : rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1977 708 : if (de->inode) {
1978 707 : struct ext4_dir_entry_2 *de1 =
1979 707 : (struct ext4_dir_entry_2 *)((char *)de + nlen);
1980 707 : de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
1981 707 : de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
1982 707 : de = de1;
1983 : }
1984 708 : de->file_type = EXT4_FT_UNKNOWN;
1985 708 : de->inode = cpu_to_le32(inode->i_ino);
1986 708 : ext4_set_de_type(inode->i_sb, de, inode->i_mode);
1987 708 : de->name_len = fname_len(fname);
1988 708 : memcpy(de->name, fname_name(fname), fname_len(fname));
1989 708 : }
1990 :
1991 : /*
1992 : * Add a new entry into a directory (leaf) block. If de is non-NULL,
1993 : * it points to a directory entry which is guaranteed to be large
1994 : * enough for new directory entry. If de is NULL, then
1995 : * add_dirent_to_buf will attempt search the directory block for
1996 : * space. It will return -ENOSPC if no space is available, and -EIO
1997 : * and -EEXIST if directory entry already exists.
1998 : */
1999 708 : static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
2000 : struct inode *dir,
2001 : struct inode *inode, struct ext4_dir_entry_2 *de,
2002 : struct buffer_head *bh)
2003 : {
2004 708 : unsigned int blocksize = dir->i_sb->s_blocksize;
2005 708 : int csum_size = 0;
2006 708 : int err, err2;
2007 :
2008 708 : if (ext4_has_metadata_csum(inode->i_sb))
2009 0 : csum_size = sizeof(struct ext4_dir_entry_tail);
2010 :
2011 708 : if (!de) {
2012 1416 : err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
2013 708 : blocksize - csum_size, fname, &de);
2014 708 : if (err)
2015 : return err;
2016 : }
2017 708 : BUFFER_TRACE(bh, "get_write_access");
2018 708 : err = ext4_journal_get_write_access(handle, bh);
2019 708 : if (err) {
2020 0 : ext4_std_error(dir->i_sb, err);
2021 0 : return err;
2022 : }
2023 :
2024 : /* By now the buffer is marked for journaling */
2025 708 : ext4_insert_dentry(inode, de, blocksize, fname);
2026 :
2027 : /*
2028 : * XXX shouldn't update any times until successful
2029 : * completion of syscall, but too many callers depend
2030 : * on this.
2031 : *
2032 : * XXX similarly, too many callers depend on
2033 : * ext4_new_inode() setting the times, but error
2034 : * recovery deletes the inode, so the worst that can
2035 : * happen is that the times are slightly out of date
2036 : * and/or different from the directory change time.
2037 : */
2038 708 : dir->i_mtime = dir->i_ctime = current_time(dir);
2039 708 : ext4_update_dx_flag(dir);
2040 708 : inode_inc_iversion(dir);
2041 708 : err2 = ext4_mark_inode_dirty(handle, dir);
2042 708 : BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2043 708 : err = ext4_handle_dirty_dirblock(handle, dir, bh);
2044 708 : if (err)
2045 0 : ext4_std_error(dir->i_sb, err);
2046 708 : return err ? err : err2;
2047 : }
2048 :
2049 : /*
2050 : * This converts a one block unindexed directory to a 3 block indexed
2051 : * directory, and adds the dentry to the indexed directory.
2052 : */
2053 0 : static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
2054 : struct inode *dir,
2055 : struct inode *inode, struct buffer_head *bh)
2056 : {
2057 0 : struct buffer_head *bh2;
2058 0 : struct dx_root *root;
2059 0 : struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2060 0 : struct dx_entry *entries;
2061 0 : struct ext4_dir_entry_2 *de, *de2;
2062 0 : char *data2, *top;
2063 0 : unsigned len;
2064 0 : int retval;
2065 0 : unsigned blocksize;
2066 0 : ext4_lblk_t block;
2067 0 : struct fake_dirent *fde;
2068 0 : int csum_size = 0;
2069 :
2070 0 : if (ext4_has_metadata_csum(inode->i_sb))
2071 0 : csum_size = sizeof(struct ext4_dir_entry_tail);
2072 :
2073 0 : blocksize = dir->i_sb->s_blocksize;
2074 0 : dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
2075 0 : BUFFER_TRACE(bh, "get_write_access");
2076 0 : retval = ext4_journal_get_write_access(handle, bh);
2077 0 : if (retval) {
2078 0 : ext4_std_error(dir->i_sb, retval);
2079 0 : brelse(bh);
2080 0 : return retval;
2081 : }
2082 0 : root = (struct dx_root *) bh->b_data;
2083 :
2084 : /* The 0th block becomes the root, move the dirents out */
2085 0 : fde = &root->dotdot;
2086 0 : de = (struct ext4_dir_entry_2 *)((char *)fde +
2087 0 : ext4_rec_len_from_disk(fde->rec_len, blocksize));
2088 0 : if ((char *) de >= (((char *) root) + blocksize)) {
2089 0 : EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
2090 0 : brelse(bh);
2091 0 : return -EFSCORRUPTED;
2092 : }
2093 0 : len = ((char *) root) + (blocksize - csum_size) - (char *) de;
2094 :
2095 : /* Allocate new block for the 0th block's dirents */
2096 0 : bh2 = ext4_append(handle, dir, &block);
2097 0 : if (IS_ERR(bh2)) {
2098 0 : brelse(bh);
2099 0 : return PTR_ERR(bh2);
2100 : }
2101 0 : ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
2102 0 : data2 = bh2->b_data;
2103 :
2104 0 : memcpy(data2, de, len);
2105 0 : de = (struct ext4_dir_entry_2 *) data2;
2106 0 : top = data2 + len;
2107 0 : while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
2108 : de = de2;
2109 0 : de->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
2110 : (char *) de, blocksize);
2111 :
2112 0 : if (csum_size)
2113 0 : ext4_initialize_dirent_tail(bh2, blocksize);
2114 :
2115 : /* Initialize the root; the dot dirents already exist */
2116 0 : de = (struct ext4_dir_entry_2 *) (&root->dotdot);
2117 0 : de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
2118 : blocksize);
2119 0 : memset (&root->info, 0, sizeof(root->info));
2120 0 : root->info.info_length = sizeof(root->info);
2121 0 : root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
2122 0 : entries = root->entries;
2123 0 : dx_set_block(entries, 1);
2124 0 : dx_set_count(entries, 1);
2125 0 : dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
2126 :
2127 : /* Initialize as for dx_probe */
2128 0 : fname->hinfo.hash_version = root->info.hash_version;
2129 0 : if (fname->hinfo.hash_version <= DX_HASH_TEA)
2130 0 : fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
2131 0 : fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
2132 0 : ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), &fname->hinfo);
2133 :
2134 0 : memset(frames, 0, sizeof(frames));
2135 0 : frame = frames;
2136 0 : frame->entries = entries;
2137 0 : frame->at = entries;
2138 0 : frame->bh = bh;
2139 :
2140 0 : retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
2141 0 : if (retval)
2142 0 : goto out_frames;
2143 0 : retval = ext4_handle_dirty_dirblock(handle, dir, bh2);
2144 0 : if (retval)
2145 0 : goto out_frames;
2146 :
2147 0 : de = do_split(handle,dir, &bh2, frame, &fname->hinfo);
2148 0 : if (IS_ERR(de)) {
2149 0 : retval = PTR_ERR(de);
2150 0 : goto out_frames;
2151 : }
2152 :
2153 0 : retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2);
2154 0 : out_frames:
2155 : /*
2156 : * Even if the block split failed, we have to properly write
2157 : * out all the changes we did so far. Otherwise we can end up
2158 : * with corrupted filesystem.
2159 : */
2160 0 : if (retval)
2161 0 : ext4_mark_inode_dirty(handle, dir);
2162 0 : dx_release(frames);
2163 0 : brelse(bh2);
2164 : return retval;
2165 : }
2166 :
2167 : /*
2168 : * ext4_add_entry()
2169 : *
2170 : * adds a file entry to the specified directory, using the same
2171 : * semantics as ext4_find_entry(). It returns NULL if it failed.
2172 : *
2173 : * NOTE!! The inode part of 'de' is left at 0 - which means you
2174 : * may not sleep between calling this and putting something into
2175 : * the entry, as someone else might have used it while you slept.
2176 : */
2177 708 : static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
2178 : struct inode *inode)
2179 : {
2180 708 : struct inode *dir = d_inode(dentry->d_parent);
2181 708 : struct buffer_head *bh = NULL;
2182 708 : struct ext4_dir_entry_2 *de;
2183 708 : struct super_block *sb;
2184 708 : struct ext4_filename fname;
2185 708 : int retval;
2186 708 : int dx_fallback=0;
2187 708 : unsigned blocksize;
2188 708 : ext4_lblk_t block, blocks;
2189 708 : int csum_size = 0;
2190 :
2191 708 : if (ext4_has_metadata_csum(inode->i_sb))
2192 0 : csum_size = sizeof(struct ext4_dir_entry_tail);
2193 :
2194 708 : sb = dir->i_sb;
2195 708 : blocksize = sb->s_blocksize;
2196 708 : if (!dentry->d_name.len)
2197 : return -EINVAL;
2198 :
2199 708 : if (fscrypt_is_nokey_name(dentry))
2200 : return -ENOKEY;
2201 :
2202 : #ifdef CONFIG_UNICODE
2203 : if (sb_has_strict_encoding(sb) && IS_CASEFOLDED(dir) &&
2204 : sb->s_encoding && utf8_validate(sb->s_encoding, &dentry->d_name))
2205 : return -EINVAL;
2206 : #endif
2207 :
2208 708 : retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);
2209 708 : if (retval)
2210 : return retval;
2211 :
2212 708 : if (ext4_has_inline_data(dir)) {
2213 0 : retval = ext4_try_add_inline_entry(handle, &fname, dir, inode);
2214 0 : if (retval < 0)
2215 0 : goto out;
2216 0 : if (retval == 1) {
2217 0 : retval = 0;
2218 0 : goto out;
2219 : }
2220 : }
2221 :
2222 1416 : if (is_dx(dir)) {
2223 4 : retval = ext4_dx_add_entry(handle, &fname, dir, inode);
2224 4 : if (!retval || (retval != ERR_BAD_DX_DIR))
2225 4 : goto out;
2226 : /* Can we just ignore htree data? */
2227 0 : if (ext4_has_metadata_csum(sb)) {
2228 0 : EXT4_ERROR_INODE(dir,
2229 : "Directory has corrupted htree index.");
2230 0 : retval = -EFSCORRUPTED;
2231 0 : goto out;
2232 : }
2233 0 : ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
2234 0 : dx_fallback++;
2235 0 : retval = ext4_mark_inode_dirty(handle, dir);
2236 0 : if (unlikely(retval))
2237 0 : goto out;
2238 : }
2239 704 : blocks = dir->i_size >> sb->s_blocksize_bits;
2240 704 : for (block = 0; block < blocks; block++) {
2241 704 : bh = ext4_read_dirblock(dir, block, DIRENT);
2242 704 : if (bh == NULL) {
2243 0 : bh = ext4_bread(handle, dir, block,
2244 : EXT4_GET_BLOCKS_CREATE);
2245 0 : goto add_to_new_block;
2246 : }
2247 704 : if (IS_ERR(bh)) {
2248 0 : retval = PTR_ERR(bh);
2249 0 : bh = NULL;
2250 0 : goto out;
2251 : }
2252 704 : retval = add_dirent_to_buf(handle, &fname, dir, inode,
2253 : NULL, bh);
2254 704 : if (retval != -ENOSPC)
2255 704 : goto out;
2256 :
2257 0 : if (blocks == 1 && !dx_fallback &&
2258 0 : ext4_has_feature_dir_index(sb)) {
2259 0 : retval = make_indexed_dir(handle, &fname, dir,
2260 : inode, bh);
2261 0 : bh = NULL; /* make_indexed_dir releases bh */
2262 0 : goto out;
2263 : }
2264 0 : brelse(bh);
2265 : }
2266 0 : bh = ext4_append(handle, dir, &block);
2267 0 : add_to_new_block:
2268 0 : if (IS_ERR(bh)) {
2269 0 : retval = PTR_ERR(bh);
2270 0 : bh = NULL;
2271 0 : goto out;
2272 : }
2273 0 : de = (struct ext4_dir_entry_2 *) bh->b_data;
2274 0 : de->inode = 0;
2275 0 : de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
2276 :
2277 0 : if (csum_size)
2278 0 : ext4_initialize_dirent_tail(bh, blocksize);
2279 :
2280 0 : retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);
2281 704 : out:
2282 708 : ext4_fname_free_filename(&fname);
2283 708 : brelse(bh);
2284 708 : if (retval == 0)
2285 708 : ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
2286 : return retval;
2287 : }
2288 :
2289 : /*
2290 : * Returns 0 for success, or a negative error value
2291 : */
2292 4 : static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
2293 : struct inode *dir, struct inode *inode)
2294 : {
2295 4 : struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;
2296 4 : struct dx_entry *entries, *at;
2297 4 : struct buffer_head *bh;
2298 4 : struct super_block *sb = dir->i_sb;
2299 4 : struct ext4_dir_entry_2 *de;
2300 4 : int restart;
2301 4 : int err;
2302 :
2303 4 : again:
2304 4 : restart = 0;
2305 4 : frame = dx_probe(fname, dir, NULL, frames);
2306 4 : if (IS_ERR(frame))
2307 0 : return PTR_ERR(frame);
2308 4 : entries = frame->entries;
2309 4 : at = frame->at;
2310 4 : bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT_HTREE);
2311 4 : if (IS_ERR(bh)) {
2312 0 : err = PTR_ERR(bh);
2313 0 : bh = NULL;
2314 0 : goto cleanup;
2315 : }
2316 :
2317 4 : BUFFER_TRACE(bh, "get_write_access");
2318 4 : err = ext4_journal_get_write_access(handle, bh);
2319 4 : if (err)
2320 0 : goto journal_error;
2321 :
2322 4 : err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh);
2323 4 : if (err != -ENOSPC)
2324 4 : goto cleanup;
2325 :
2326 0 : err = 0;
2327 : /* Block full, should compress but for now just split */
2328 : dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
2329 0 : dx_get_count(entries), dx_get_limit(entries)));
2330 : /* Need to split index? */
2331 0 : if (dx_get_count(entries) == dx_get_limit(entries)) {
2332 0 : ext4_lblk_t newblock;
2333 0 : int levels = frame - frames + 1;
2334 0 : unsigned int icount;
2335 0 : int add_level = 1;
2336 0 : struct dx_entry *entries2;
2337 0 : struct dx_node *node2;
2338 0 : struct buffer_head *bh2;
2339 :
2340 0 : while (frame > frames) {
2341 0 : if (dx_get_count((frame - 1)->entries) <
2342 0 : dx_get_limit((frame - 1)->entries)) {
2343 : add_level = 0;
2344 : break;
2345 : }
2346 0 : frame--; /* split higher index block */
2347 0 : at = frame->at;
2348 0 : entries = frame->entries;
2349 0 : restart = 1;
2350 : }
2351 0 : if (add_level && levels == ext4_dir_htree_level(sb)) {
2352 0 : ext4_warning(sb, "Directory (ino: %lu) index full, "
2353 : "reach max htree level :%d",
2354 : dir->i_ino, levels);
2355 0 : if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) {
2356 0 : ext4_warning(sb, "Large directory feature is "
2357 : "not enabled on this "
2358 : "filesystem");
2359 : }
2360 0 : err = -ENOSPC;
2361 0 : goto cleanup;
2362 : }
2363 0 : icount = dx_get_count(entries);
2364 0 : bh2 = ext4_append(handle, dir, &newblock);
2365 0 : if (IS_ERR(bh2)) {
2366 0 : err = PTR_ERR(bh2);
2367 0 : goto cleanup;
2368 : }
2369 0 : node2 = (struct dx_node *)(bh2->b_data);
2370 0 : entries2 = node2->entries;
2371 0 : memset(&node2->fake, 0, sizeof(struct fake_dirent));
2372 0 : node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
2373 0 : sb->s_blocksize);
2374 0 : BUFFER_TRACE(frame->bh, "get_write_access");
2375 0 : err = ext4_journal_get_write_access(handle, frame->bh);
2376 0 : if (err)
2377 0 : goto journal_error;
2378 0 : if (!add_level) {
2379 0 : unsigned icount1 = icount/2, icount2 = icount - icount1;
2380 0 : unsigned hash2 = dx_get_hash(entries + icount1);
2381 : dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2382 0 : icount1, icount2));
2383 :
2384 0 : BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
2385 0 : err = ext4_journal_get_write_access(handle,
2386 : (frame - 1)->bh);
2387 0 : if (err)
2388 0 : goto journal_error;
2389 :
2390 0 : memcpy((char *) entries2, (char *) (entries + icount1),
2391 : icount2 * sizeof(struct dx_entry));
2392 0 : dx_set_count(entries, icount1);
2393 0 : dx_set_count(entries2, icount2);
2394 0 : dx_set_limit(entries2, dx_node_limit(dir));
2395 :
2396 : /* Which index block gets the new entry? */
2397 0 : if (at - entries >= icount1) {
2398 0 : frame->at = at = at - entries - icount1 + entries2;
2399 0 : frame->entries = entries = entries2;
2400 0 : swap(frame->bh, bh2);
2401 : }
2402 0 : dx_insert_block((frame - 1), hash2, newblock);
2403 0 : dxtrace(dx_show_index("node", frame->entries));
2404 : dxtrace(dx_show_index("node",
2405 0 : ((struct dx_node *) bh2->b_data)->entries));
2406 0 : err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2407 0 : if (err)
2408 0 : goto journal_error;
2409 0 : brelse (bh2);
2410 0 : err = ext4_handle_dirty_dx_node(handle, dir,
2411 : (frame - 1)->bh);
2412 0 : if (err)
2413 0 : goto journal_error;
2414 0 : err = ext4_handle_dirty_dx_node(handle, dir,
2415 : frame->bh);
2416 0 : if (err)
2417 0 : goto journal_error;
2418 : } else {
2419 0 : struct dx_root *dxroot;
2420 0 : memcpy((char *) entries2, (char *) entries,
2421 : icount * sizeof(struct dx_entry));
2422 0 : dx_set_limit(entries2, dx_node_limit(dir));
2423 :
2424 : /* Set up root */
2425 0 : dx_set_count(entries, 1);
2426 0 : dx_set_block(entries + 0, newblock);
2427 0 : dxroot = (struct dx_root *)frames[0].bh->b_data;
2428 0 : dxroot->info.indirect_levels += 1;
2429 : dxtrace(printk(KERN_DEBUG
2430 : "Creating %d level index...\n",
2431 0 : dxroot->info.indirect_levels));
2432 0 : err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
2433 0 : if (err)
2434 0 : goto journal_error;
2435 0 : err = ext4_handle_dirty_dx_node(handle, dir, bh2);
2436 0 : brelse(bh2);
2437 0 : restart = 1;
2438 0 : goto journal_error;
2439 : }
2440 : }
2441 0 : de = do_split(handle, dir, &bh, frame, &fname->hinfo);
2442 0 : if (IS_ERR(de)) {
2443 0 : err = PTR_ERR(de);
2444 0 : goto cleanup;
2445 : }
2446 0 : err = add_dirent_to_buf(handle, fname, dir, inode, de, bh);
2447 0 : goto cleanup;
2448 :
2449 0 : journal_error:
2450 0 : ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */
2451 0 : cleanup:
2452 4 : brelse(bh);
2453 4 : dx_release(frames);
2454 : /* @restart is true means htree-path has been changed, we need to
2455 : * repeat dx_probe() to find out valid htree-path
2456 : */
2457 4 : if (restart && err == 0)
2458 0 : goto again;
2459 : return err;
2460 : }
2461 :
2462 : /*
2463 : * ext4_generic_delete_entry deletes a directory entry by merging it
2464 : * with the previous entry
2465 : */
2466 264 : int ext4_generic_delete_entry(struct inode *dir,
2467 : struct ext4_dir_entry_2 *de_del,
2468 : struct buffer_head *bh,
2469 : void *entry_buf,
2470 : int buf_size,
2471 : int csum_size)
2472 : {
2473 264 : struct ext4_dir_entry_2 *de, *pde;
2474 264 : unsigned int blocksize = dir->i_sb->s_blocksize;
2475 264 : int i;
2476 :
2477 264 : i = 0;
2478 264 : pde = NULL;
2479 264 : de = (struct ext4_dir_entry_2 *)entry_buf;
2480 5979 : while (i < buf_size - csum_size) {
2481 5979 : if (ext4_check_dir_entry(dir, NULL, de, bh,
2482 : entry_buf, buf_size, i))
2483 : return -EFSCORRUPTED;
2484 5979 : if (de == de_del) {
2485 264 : if (pde)
2486 264 : pde->rec_len = ext4_rec_len_to_disk(
2487 264 : ext4_rec_len_from_disk(pde->rec_len,
2488 : blocksize) +
2489 264 : ext4_rec_len_from_disk(de->rec_len,
2490 : blocksize),
2491 : blocksize);
2492 : else
2493 0 : de->inode = 0;
2494 264 : inode_inc_iversion(dir);
2495 264 : return 0;
2496 : }
2497 5715 : i += ext4_rec_len_from_disk(de->rec_len, blocksize);
2498 5715 : pde = de;
2499 5715 : de = ext4_next_entry(de, blocksize);
2500 : }
2501 : return -ENOENT;
2502 : }
2503 :
2504 264 : static int ext4_delete_entry(handle_t *handle,
2505 : struct inode *dir,
2506 : struct ext4_dir_entry_2 *de_del,
2507 : struct buffer_head *bh)
2508 : {
2509 264 : int err, csum_size = 0;
2510 :
2511 264 : if (ext4_has_inline_data(dir)) {
2512 0 : int has_inline_data = 1;
2513 0 : err = ext4_delete_inline_entry(handle, dir, de_del, bh,
2514 : &has_inline_data);
2515 0 : if (has_inline_data)
2516 0 : return err;
2517 : }
2518 :
2519 264 : if (ext4_has_metadata_csum(dir->i_sb))
2520 0 : csum_size = sizeof(struct ext4_dir_entry_tail);
2521 :
2522 264 : BUFFER_TRACE(bh, "get_write_access");
2523 264 : err = ext4_journal_get_write_access(handle, bh);
2524 264 : if (unlikely(err))
2525 0 : goto out;
2526 :
2527 528 : err = ext4_generic_delete_entry(dir, de_del, bh, bh->b_data,
2528 264 : dir->i_sb->s_blocksize, csum_size);
2529 264 : if (err)
2530 0 : goto out;
2531 :
2532 264 : BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2533 264 : err = ext4_handle_dirty_dirblock(handle, dir, bh);
2534 264 : if (unlikely(err))
2535 0 : goto out;
2536 :
2537 : return 0;
2538 0 : out:
2539 0 : if (err != -ENOENT)
2540 0 : ext4_std_error(dir->i_sb, err);
2541 : return err;
2542 : }
2543 :
2544 : /*
2545 : * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2
2546 : * since this indicates that nlinks count was previously 1 to avoid overflowing
2547 : * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean
2548 : * that subdirectory link counts are not being maintained accurately.
2549 : *
2550 : * The caller has already checked for i_nlink overflow in case the DIR_LINK
2551 : * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy
2552 : * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set
2553 : * on regular files) and to avoid creating huge/slow non-HTREE directories.
2554 : */
2555 173 : static void ext4_inc_count(struct inode *inode)
2556 : {
2557 173 : inc_nlink(inode);
2558 346 : if (is_dx(inode) &&
2559 2 : (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))
2560 0 : set_nlink(inode, 1);
2561 173 : }
2562 :
2563 : /*
2564 : * If a directory had nlink == 1, then we should let it be 1. This indicates
2565 : * directory has >EXT4_LINK_MAX subdirs.
2566 : */
2567 101 : static void ext4_dec_count(struct inode *inode)
2568 : {
2569 101 : if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2570 101 : drop_nlink(inode);
2571 101 : }
2572 :
2573 :
2574 : /*
2575 : * Add non-directory inode to a directory. On success, the inode reference is
2576 : * consumed by dentry is instantiation. This is also indicated by clearing of
2577 : * *inodep pointer. On failure, the caller is responsible for dropping the
2578 : * inode reference in the safe context.
2579 : */
2580 464 : static int ext4_add_nondir(handle_t *handle,
2581 : struct dentry *dentry, struct inode **inodep)
2582 : {
2583 464 : struct inode *dir = d_inode(dentry->d_parent);
2584 464 : struct inode *inode = *inodep;
2585 464 : int err = ext4_add_entry(handle, dentry, inode);
2586 464 : if (!err) {
2587 464 : err = ext4_mark_inode_dirty(handle, inode);
2588 464 : if (IS_DIRSYNC(dir))
2589 0 : ext4_handle_sync(handle);
2590 464 : d_instantiate_new(dentry, inode);
2591 464 : *inodep = NULL;
2592 464 : return err;
2593 : }
2594 0 : drop_nlink(inode);
2595 0 : ext4_orphan_add(handle, inode);
2596 0 : unlock_new_inode(inode);
2597 0 : return err;
2598 : }
2599 :
2600 : /*
2601 : * By the time this is called, we already have created
2602 : * the directory cache entry for the new file, but it
2603 : * is so far negative - it has no inode.
2604 : *
2605 : * If the create succeeds, we fill in the inode information
2606 : * with d_instantiate().
2607 : */
2608 464 : static int ext4_create(struct user_namespace *mnt_userns, struct inode *dir,
2609 : struct dentry *dentry, umode_t mode, bool excl)
2610 : {
2611 464 : handle_t *handle;
2612 464 : struct inode *inode;
2613 464 : int err, credits, retries = 0;
2614 :
2615 464 : err = dquot_initialize(dir);
2616 464 : if (err)
2617 : return err;
2618 :
2619 464 : credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2620 464 : EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2621 464 : retry:
2622 464 : inode = ext4_new_inode_start_handle(mnt_userns, dir, mode, &dentry->d_name,
2623 : 0, NULL, EXT4_HT_DIR, credits);
2624 464 : handle = ext4_journal_current_handle();
2625 464 : err = PTR_ERR(inode);
2626 464 : if (!IS_ERR(inode)) {
2627 464 : inode->i_op = &ext4_file_inode_operations;
2628 464 : inode->i_fop = &ext4_file_operations;
2629 464 : ext4_set_aops(inode);
2630 464 : err = ext4_add_nondir(handle, dentry, &inode);
2631 464 : if (!err)
2632 464 : ext4_fc_track_create(handle, dentry);
2633 : }
2634 464 : if (handle)
2635 464 : ext4_journal_stop(handle);
2636 464 : if (!IS_ERR_OR_NULL(inode))
2637 0 : iput(inode);
2638 464 : if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2639 0 : goto retry;
2640 464 : return err;
2641 : }
2642 :
2643 0 : static int ext4_mknod(struct user_namespace *mnt_userns, struct inode *dir,
2644 : struct dentry *dentry, umode_t mode, dev_t rdev)
2645 : {
2646 0 : handle_t *handle;
2647 0 : struct inode *inode;
2648 0 : int err, credits, retries = 0;
2649 :
2650 0 : err = dquot_initialize(dir);
2651 0 : if (err)
2652 : return err;
2653 :
2654 0 : credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2655 0 : EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2656 0 : retry:
2657 0 : inode = ext4_new_inode_start_handle(mnt_userns, dir, mode, &dentry->d_name,
2658 : 0, NULL, EXT4_HT_DIR, credits);
2659 0 : handle = ext4_journal_current_handle();
2660 0 : err = PTR_ERR(inode);
2661 0 : if (!IS_ERR(inode)) {
2662 0 : init_special_inode(inode, inode->i_mode, rdev);
2663 0 : inode->i_op = &ext4_special_inode_operations;
2664 0 : err = ext4_add_nondir(handle, dentry, &inode);
2665 0 : if (!err)
2666 0 : ext4_fc_track_create(handle, dentry);
2667 : }
2668 0 : if (handle)
2669 0 : ext4_journal_stop(handle);
2670 0 : if (!IS_ERR_OR_NULL(inode))
2671 0 : iput(inode);
2672 0 : if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2673 0 : goto retry;
2674 0 : return err;
2675 : }
2676 :
2677 0 : static int ext4_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
2678 : struct dentry *dentry, umode_t mode)
2679 : {
2680 0 : handle_t *handle;
2681 0 : struct inode *inode;
2682 0 : int err, retries = 0;
2683 :
2684 0 : err = dquot_initialize(dir);
2685 0 : if (err)
2686 : return err;
2687 :
2688 0 : retry:
2689 0 : inode = ext4_new_inode_start_handle(mnt_userns, dir, mode,
2690 : NULL, 0, NULL,
2691 : EXT4_HT_DIR,
2692 : EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2693 : 4 + EXT4_XATTR_TRANS_BLOCKS);
2694 0 : handle = ext4_journal_current_handle();
2695 0 : err = PTR_ERR(inode);
2696 0 : if (!IS_ERR(inode)) {
2697 0 : inode->i_op = &ext4_file_inode_operations;
2698 0 : inode->i_fop = &ext4_file_operations;
2699 0 : ext4_set_aops(inode);
2700 0 : d_tmpfile(dentry, inode);
2701 0 : err = ext4_orphan_add(handle, inode);
2702 0 : if (err)
2703 0 : goto err_unlock_inode;
2704 0 : mark_inode_dirty(inode);
2705 0 : unlock_new_inode(inode);
2706 : }
2707 0 : if (handle)
2708 0 : ext4_journal_stop(handle);
2709 0 : if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2710 0 : goto retry;
2711 : return err;
2712 0 : err_unlock_inode:
2713 0 : ext4_journal_stop(handle);
2714 0 : unlock_new_inode(inode);
2715 0 : return err;
2716 : }
2717 :
2718 173 : struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2719 : struct ext4_dir_entry_2 *de,
2720 : int blocksize, int csum_size,
2721 : unsigned int parent_ino, int dotdot_real_len)
2722 : {
2723 173 : de->inode = cpu_to_le32(inode->i_ino);
2724 173 : de->name_len = 1;
2725 173 : de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2726 : blocksize);
2727 173 : strcpy(de->name, ".");
2728 173 : ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2729 :
2730 173 : de = ext4_next_entry(de, blocksize);
2731 173 : de->inode = cpu_to_le32(parent_ino);
2732 173 : de->name_len = 2;
2733 173 : if (!dotdot_real_len)
2734 173 : de->rec_len = ext4_rec_len_to_disk(blocksize -
2735 : (csum_size + EXT4_DIR_REC_LEN(1)),
2736 : blocksize);
2737 : else
2738 0 : de->rec_len = ext4_rec_len_to_disk(
2739 : EXT4_DIR_REC_LEN(de->name_len), blocksize);
2740 173 : strcpy(de->name, "..");
2741 173 : ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2742 :
2743 173 : return ext4_next_entry(de, blocksize);
2744 : }
2745 :
2746 173 : int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2747 : struct inode *inode)
2748 : {
2749 173 : struct buffer_head *dir_block = NULL;
2750 173 : struct ext4_dir_entry_2 *de;
2751 173 : ext4_lblk_t block = 0;
2752 173 : unsigned int blocksize = dir->i_sb->s_blocksize;
2753 173 : int csum_size = 0;
2754 173 : int err;
2755 :
2756 173 : if (ext4_has_metadata_csum(dir->i_sb))
2757 0 : csum_size = sizeof(struct ext4_dir_entry_tail);
2758 :
2759 173 : if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
2760 0 : err = ext4_try_create_inline_dir(handle, dir, inode);
2761 0 : if (err < 0 && err != -ENOSPC)
2762 0 : goto out;
2763 0 : if (!err)
2764 0 : goto out;
2765 : }
2766 :
2767 173 : inode->i_size = 0;
2768 173 : dir_block = ext4_append(handle, inode, &block);
2769 173 : if (IS_ERR(dir_block))
2770 0 : return PTR_ERR(dir_block);
2771 173 : de = (struct ext4_dir_entry_2 *)dir_block->b_data;
2772 173 : ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
2773 173 : set_nlink(inode, 2);
2774 173 : if (csum_size)
2775 0 : ext4_initialize_dirent_tail(dir_block, blocksize);
2776 :
2777 173 : BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2778 173 : err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
2779 173 : if (err)
2780 0 : goto out;
2781 173 : set_buffer_verified(dir_block);
2782 173 : out:
2783 173 : brelse(dir_block);
2784 : return err;
2785 : }
2786 :
2787 173 : static int ext4_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
2788 : struct dentry *dentry, umode_t mode)
2789 : {
2790 173 : handle_t *handle;
2791 173 : struct inode *inode;
2792 173 : int err, err2 = 0, credits, retries = 0;
2793 :
2794 173 : if (EXT4_DIR_LINK_MAX(dir))
2795 0 : return -EMLINK;
2796 :
2797 173 : err = dquot_initialize(dir);
2798 173 : if (err)
2799 : return err;
2800 :
2801 173 : credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2802 173 : EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
2803 173 : retry:
2804 173 : inode = ext4_new_inode_start_handle(mnt_userns, dir, S_IFDIR | mode,
2805 : &dentry->d_name,
2806 : 0, NULL, EXT4_HT_DIR, credits);
2807 173 : handle = ext4_journal_current_handle();
2808 173 : err = PTR_ERR(inode);
2809 173 : if (IS_ERR(inode))
2810 0 : goto out_stop;
2811 :
2812 173 : inode->i_op = &ext4_dir_inode_operations;
2813 173 : inode->i_fop = &ext4_dir_operations;
2814 173 : err = ext4_init_new_dir(handle, dir, inode);
2815 173 : if (err)
2816 0 : goto out_clear_inode;
2817 173 : err = ext4_mark_inode_dirty(handle, inode);
2818 173 : if (!err)
2819 173 : err = ext4_add_entry(handle, dentry, inode);
2820 173 : if (err) {
2821 0 : out_clear_inode:
2822 0 : clear_nlink(inode);
2823 0 : ext4_orphan_add(handle, inode);
2824 0 : unlock_new_inode(inode);
2825 0 : err2 = ext4_mark_inode_dirty(handle, inode);
2826 0 : if (unlikely(err2))
2827 0 : err = err2;
2828 0 : ext4_journal_stop(handle);
2829 0 : iput(inode);
2830 0 : goto out_retry;
2831 : }
2832 173 : ext4_inc_count(dir);
2833 :
2834 173 : ext4_update_dx_flag(dir);
2835 173 : err = ext4_mark_inode_dirty(handle, dir);
2836 173 : if (err)
2837 0 : goto out_clear_inode;
2838 173 : d_instantiate_new(dentry, inode);
2839 173 : ext4_fc_track_create(handle, dentry);
2840 173 : if (IS_DIRSYNC(dir))
2841 0 : ext4_handle_sync(handle);
2842 :
2843 173 : out_stop:
2844 173 : if (handle)
2845 173 : ext4_journal_stop(handle);
2846 0 : out_retry:
2847 173 : if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2848 0 : goto retry;
2849 : return err;
2850 : }
2851 :
2852 : /*
2853 : * routine to check that the specified directory is empty (for rmdir)
2854 : */
2855 71 : bool ext4_empty_dir(struct inode *inode)
2856 : {
2857 71 : unsigned int offset;
2858 71 : struct buffer_head *bh;
2859 71 : struct ext4_dir_entry_2 *de;
2860 71 : struct super_block *sb;
2861 :
2862 71 : if (ext4_has_inline_data(inode)) {
2863 0 : int has_inline_data = 1;
2864 0 : int ret;
2865 :
2866 0 : ret = empty_inline_dir(inode, &has_inline_data);
2867 0 : if (has_inline_data)
2868 0 : return ret;
2869 : }
2870 :
2871 71 : sb = inode->i_sb;
2872 71 : if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
2873 0 : EXT4_ERROR_INODE(inode, "invalid size");
2874 0 : return true;
2875 : }
2876 : /* The first directory block must not be a hole,
2877 : * so treat it as DIRENT_HTREE
2878 : */
2879 71 : bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE);
2880 71 : if (IS_ERR(bh))
2881 : return true;
2882 :
2883 71 : de = (struct ext4_dir_entry_2 *) bh->b_data;
2884 71 : if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
2885 71 : 0) ||
2886 71 : le32_to_cpu(de->inode) != inode->i_ino || strcmp(".", de->name)) {
2887 0 : ext4_warning_inode(inode, "directory missing '.'");
2888 0 : brelse(bh);
2889 0 : return true;
2890 : }
2891 71 : offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2892 71 : de = ext4_next_entry(de, sb->s_blocksize);
2893 71 : if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,
2894 71 : offset) ||
2895 71 : le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) {
2896 0 : ext4_warning_inode(inode, "directory missing '..'");
2897 0 : brelse(bh);
2898 0 : return true;
2899 : }
2900 71 : offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2901 71 : while (offset < inode->i_size) {
2902 0 : if (!(offset & (sb->s_blocksize - 1))) {
2903 0 : unsigned int lblock;
2904 0 : brelse(bh);
2905 0 : lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
2906 0 : bh = ext4_read_dirblock(inode, lblock, EITHER);
2907 0 : if (bh == NULL) {
2908 0 : offset += sb->s_blocksize;
2909 0 : continue;
2910 : }
2911 0 : if (IS_ERR(bh))
2912 : return true;
2913 : }
2914 0 : de = (struct ext4_dir_entry_2 *) (bh->b_data +
2915 0 : (offset & (sb->s_blocksize - 1)));
2916 0 : if (ext4_check_dir_entry(inode, NULL, de, bh,
2917 : bh->b_data, bh->b_size, offset)) {
2918 0 : offset = (offset | (sb->s_blocksize - 1)) + 1;
2919 0 : continue;
2920 : }
2921 0 : if (le32_to_cpu(de->inode)) {
2922 0 : brelse(bh);
2923 0 : return false;
2924 : }
2925 0 : offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2926 : }
2927 71 : brelse(bh);
2928 : return true;
2929 : }
2930 :
2931 : /*
2932 : * ext4_orphan_add() links an unlinked or truncated inode into a list of
2933 : * such inodes, starting at the superblock, in case we crash before the
2934 : * file is closed/deleted, or in case the inode truncate spans multiple
2935 : * transactions and the last transaction is not recovered after a crash.
2936 : *
2937 : * At filesystem recovery time, we walk this list deleting unlinked
2938 : * inodes and truncating linked inodes in ext4_orphan_cleanup().
2939 : *
2940 : * Orphan list manipulation functions must be called under i_mutex unless
2941 : * we are just creating the inode or deleting it.
2942 : */
2943 334 : int ext4_orphan_add(handle_t *handle, struct inode *inode)
2944 : {
2945 334 : struct super_block *sb = inode->i_sb;
2946 334 : struct ext4_sb_info *sbi = EXT4_SB(sb);
2947 334 : struct ext4_iloc iloc;
2948 334 : int err = 0, rc;
2949 334 : bool dirty = false;
2950 :
2951 334 : if (!sbi->s_journal || is_bad_inode(inode))
2952 0 : return 0;
2953 :
2954 732 : WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
2955 : !inode_is_locked(inode));
2956 : /*
2957 : * Exit early if inode already is on orphan list. This is a big speedup
2958 : * since we don't have to contend on the global s_orphan_lock.
2959 : */
2960 334 : if (!list_empty(&EXT4_I(inode)->i_orphan))
2961 : return 0;
2962 :
2963 : /*
2964 : * Orphan handling is only valid for files with data blocks
2965 : * being truncated, or files being unlinked. Note that we either
2966 : * hold i_mutex, or the inode can not be referenced from outside,
2967 : * so i_nlink should not be bumped due to race
2968 : */
2969 198 : ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2970 : S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
2971 :
2972 198 : BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2973 198 : err = ext4_journal_get_write_access(handle, sbi->s_sbh);
2974 198 : if (err)
2975 0 : goto out;
2976 :
2977 198 : err = ext4_reserve_inode_write(handle, inode, &iloc);
2978 198 : if (err)
2979 0 : goto out;
2980 :
2981 198 : mutex_lock(&sbi->s_orphan_lock);
2982 : /*
2983 : * Due to previous errors inode may be already a part of on-disk
2984 : * orphan list. If so skip on-disk list modification.
2985 : */
2986 198 : if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
2987 0 : (le32_to_cpu(sbi->s_es->s_inodes_count))) {
2988 : /* Insert this inode at the head of the on-disk orphan list */
2989 198 : NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
2990 198 : lock_buffer(sbi->s_sbh);
2991 198 : sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2992 198 : ext4_superblock_csum_set(sb);
2993 198 : unlock_buffer(sbi->s_sbh);
2994 198 : dirty = true;
2995 : }
2996 198 : list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
2997 198 : mutex_unlock(&sbi->s_orphan_lock);
2998 :
2999 198 : if (dirty) {
3000 198 : err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
3001 198 : rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
3002 198 : if (!err)
3003 198 : err = rc;
3004 198 : if (err) {
3005 : /*
3006 : * We have to remove inode from in-memory list if
3007 : * addition to on disk orphan list failed. Stray orphan
3008 : * list entries can cause panics at unmount time.
3009 : */
3010 0 : mutex_lock(&sbi->s_orphan_lock);
3011 0 : list_del_init(&EXT4_I(inode)->i_orphan);
3012 0 : mutex_unlock(&sbi->s_orphan_lock);
3013 : }
3014 : } else
3015 0 : brelse(iloc.bh);
3016 :
3017 198 : jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
3018 : jbd_debug(4, "orphan inode %lu will point to %d\n",
3019 198 : inode->i_ino, NEXT_ORPHAN(inode));
3020 198 : out:
3021 198 : ext4_std_error(sb, err);
3022 : return err;
3023 : }
3024 :
3025 : /*
3026 : * ext4_orphan_del() removes an unlinked or truncated inode from the list
3027 : * of such inodes stored on disk, because it is finally being cleaned up.
3028 : */
3029 199 : int ext4_orphan_del(handle_t *handle, struct inode *inode)
3030 : {
3031 199 : struct list_head *prev;
3032 199 : struct ext4_inode_info *ei = EXT4_I(inode);
3033 199 : struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
3034 199 : __u32 ino_next;
3035 199 : struct ext4_iloc iloc;
3036 199 : int err = 0;
3037 :
3038 199 : if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
3039 : return 0;
3040 :
3041 211 : WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
3042 : !inode_is_locked(inode));
3043 : /* Do this quick check before taking global s_orphan_lock. */
3044 199 : if (list_empty(&ei->i_orphan))
3045 : return 0;
3046 :
3047 198 : if (handle) {
3048 : /* Grab inode buffer early before taking global s_orphan_lock */
3049 198 : err = ext4_reserve_inode_write(handle, inode, &iloc);
3050 : }
3051 :
3052 198 : mutex_lock(&sbi->s_orphan_lock);
3053 198 : jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
3054 :
3055 198 : prev = ei->i_orphan.prev;
3056 198 : list_del_init(&ei->i_orphan);
3057 :
3058 : /* If we're on an error path, we may not have a valid
3059 : * transaction handle with which to update the orphan list on
3060 : * disk, but we still need to remove the inode from the linked
3061 : * list in memory. */
3062 198 : if (!handle || err) {
3063 0 : mutex_unlock(&sbi->s_orphan_lock);
3064 0 : goto out_err;
3065 : }
3066 :
3067 198 : ino_next = NEXT_ORPHAN(inode);
3068 198 : if (prev == &sbi->s_orphan) {
3069 198 : jbd_debug(4, "superblock will point to %u\n", ino_next);
3070 198 : BUFFER_TRACE(sbi->s_sbh, "get_write_access");
3071 198 : err = ext4_journal_get_write_access(handle, sbi->s_sbh);
3072 198 : if (err) {
3073 0 : mutex_unlock(&sbi->s_orphan_lock);
3074 0 : goto out_brelse;
3075 : }
3076 198 : lock_buffer(sbi->s_sbh);
3077 198 : sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
3078 198 : ext4_superblock_csum_set(inode->i_sb);
3079 198 : unlock_buffer(sbi->s_sbh);
3080 198 : mutex_unlock(&sbi->s_orphan_lock);
3081 198 : err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
3082 : } else {
3083 0 : struct ext4_iloc iloc2;
3084 0 : struct inode *i_prev =
3085 0 : &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
3086 :
3087 : jbd_debug(4, "orphan inode %lu will point to %u\n",
3088 0 : i_prev->i_ino, ino_next);
3089 0 : err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
3090 0 : if (err) {
3091 0 : mutex_unlock(&sbi->s_orphan_lock);
3092 0 : goto out_brelse;
3093 : }
3094 0 : NEXT_ORPHAN(i_prev) = ino_next;
3095 0 : err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
3096 0 : mutex_unlock(&sbi->s_orphan_lock);
3097 : }
3098 198 : if (err)
3099 0 : goto out_brelse;
3100 198 : NEXT_ORPHAN(inode) = 0;
3101 198 : err = ext4_mark_iloc_dirty(handle, inode, &iloc);
3102 198 : out_err:
3103 198 : ext4_std_error(inode->i_sb, err);
3104 : return err;
3105 :
3106 0 : out_brelse:
3107 0 : brelse(iloc.bh);
3108 0 : goto out_err;
3109 : }
3110 :
3111 71 : static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
3112 : {
3113 71 : int retval;
3114 71 : struct inode *inode;
3115 71 : struct buffer_head *bh;
3116 71 : struct ext4_dir_entry_2 *de;
3117 71 : handle_t *handle = NULL;
3118 :
3119 71 : if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3120 : return -EIO;
3121 :
3122 : /* Initialize quotas before so that eventual writes go in
3123 : * separate transaction */
3124 71 : retval = dquot_initialize(dir);
3125 71 : if (retval)
3126 : return retval;
3127 71 : retval = dquot_initialize(d_inode(dentry));
3128 71 : if (retval)
3129 : return retval;
3130 :
3131 71 : retval = -ENOENT;
3132 71 : bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
3133 71 : if (IS_ERR(bh))
3134 0 : return PTR_ERR(bh);
3135 71 : if (!bh)
3136 0 : goto end_rmdir;
3137 :
3138 71 : inode = d_inode(dentry);
3139 :
3140 71 : retval = -EFSCORRUPTED;
3141 71 : if (le32_to_cpu(de->inode) != inode->i_ino)
3142 0 : goto end_rmdir;
3143 :
3144 71 : retval = -ENOTEMPTY;
3145 71 : if (!ext4_empty_dir(inode))
3146 0 : goto end_rmdir;
3147 :
3148 71 : handle = ext4_journal_start(dir, EXT4_HT_DIR,
3149 : EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3150 71 : if (IS_ERR(handle)) {
3151 0 : retval = PTR_ERR(handle);
3152 0 : handle = NULL;
3153 0 : goto end_rmdir;
3154 : }
3155 :
3156 71 : if (IS_DIRSYNC(dir))
3157 0 : ext4_handle_sync(handle);
3158 :
3159 71 : retval = ext4_delete_entry(handle, dir, de, bh);
3160 71 : if (retval)
3161 0 : goto end_rmdir;
3162 71 : if (!EXT4_DIR_LINK_EMPTY(inode))
3163 0 : ext4_warning_inode(inode,
3164 : "empty directory '%.*s' has too many links (%u)",
3165 : dentry->d_name.len, dentry->d_name.name,
3166 : inode->i_nlink);
3167 71 : inode_inc_iversion(inode);
3168 71 : clear_nlink(inode);
3169 : /* There's no need to set i_disksize: the fact that i_nlink is
3170 : * zero will ensure that the right thing happens during any
3171 : * recovery. */
3172 71 : inode->i_size = 0;
3173 71 : ext4_orphan_add(handle, inode);
3174 71 : inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode);
3175 71 : retval = ext4_mark_inode_dirty(handle, inode);
3176 71 : if (retval)
3177 0 : goto end_rmdir;
3178 71 : ext4_dec_count(dir);
3179 71 : ext4_update_dx_flag(dir);
3180 71 : ext4_fc_track_unlink(handle, dentry);
3181 71 : retval = ext4_mark_inode_dirty(handle, dir);
3182 :
3183 : #ifdef CONFIG_UNICODE
3184 : /* VFS negative dentries are incompatible with Encoding and
3185 : * Case-insensitiveness. Eventually we'll want avoid
3186 : * invalidating the dentries here, alongside with returning the
3187 : * negative dentries at ext4_lookup(), when it is better
3188 : * supported by the VFS for the CI case.
3189 : */
3190 : if (IS_CASEFOLDED(dir))
3191 : d_invalidate(dentry);
3192 : #endif
3193 :
3194 71 : end_rmdir:
3195 71 : brelse(bh);
3196 71 : if (handle)
3197 71 : ext4_journal_stop(handle);
3198 : return retval;
3199 : }
3200 :
3201 92 : int __ext4_unlink(handle_t *handle, struct inode *dir, const struct qstr *d_name,
3202 : struct inode *inode)
3203 : {
3204 92 : int retval = -ENOENT;
3205 92 : struct buffer_head *bh;
3206 92 : struct ext4_dir_entry_2 *de;
3207 92 : int skip_remove_dentry = 0;
3208 :
3209 92 : bh = ext4_find_entry(dir, d_name, &de, NULL);
3210 92 : if (IS_ERR(bh))
3211 0 : return PTR_ERR(bh);
3212 :
3213 92 : if (!bh)
3214 : return -ENOENT;
3215 :
3216 92 : if (le32_to_cpu(de->inode) != inode->i_ino) {
3217 : /*
3218 : * It's okay if we find dont find dentry which matches
3219 : * the inode. That's because it might have gotten
3220 : * renamed to a different inode number
3221 : */
3222 0 : if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
3223 : skip_remove_dentry = 1;
3224 : else
3225 0 : goto out;
3226 : }
3227 :
3228 92 : if (IS_DIRSYNC(dir))
3229 0 : ext4_handle_sync(handle);
3230 :
3231 92 : if (!skip_remove_dentry) {
3232 92 : retval = ext4_delete_entry(handle, dir, de, bh);
3233 92 : if (retval)
3234 0 : goto out;
3235 92 : dir->i_ctime = dir->i_mtime = current_time(dir);
3236 92 : ext4_update_dx_flag(dir);
3237 92 : retval = ext4_mark_inode_dirty(handle, dir);
3238 92 : if (retval)
3239 0 : goto out;
3240 : } else {
3241 92 : retval = 0;
3242 : }
3243 92 : if (inode->i_nlink == 0)
3244 0 : ext4_warning_inode(inode, "Deleting file '%.*s' with no links",
3245 : d_name->len, d_name->name);
3246 : else
3247 92 : drop_nlink(inode);
3248 92 : if (!inode->i_nlink)
3249 92 : ext4_orphan_add(handle, inode);
3250 92 : inode->i_ctime = current_time(inode);
3251 92 : retval = ext4_mark_inode_dirty(handle, inode);
3252 :
3253 92 : out:
3254 92 : brelse(bh);
3255 92 : return retval;
3256 : }
3257 :
3258 92 : static int ext4_unlink(struct inode *dir, struct dentry *dentry)
3259 : {
3260 92 : handle_t *handle;
3261 92 : int retval;
3262 :
3263 92 : if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3264 : return -EIO;
3265 :
3266 92 : trace_ext4_unlink_enter(dir, dentry);
3267 : /*
3268 : * Initialize quotas before so that eventual writes go
3269 : * in separate transaction
3270 : */
3271 92 : retval = dquot_initialize(dir);
3272 92 : if (retval)
3273 : goto out_trace;
3274 92 : retval = dquot_initialize(d_inode(dentry));
3275 92 : if (retval)
3276 : goto out_trace;
3277 :
3278 92 : handle = ext4_journal_start(dir, EXT4_HT_DIR,
3279 : EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
3280 92 : if (IS_ERR(handle)) {
3281 0 : retval = PTR_ERR(handle);
3282 0 : goto out_trace;
3283 : }
3284 :
3285 92 : retval = __ext4_unlink(handle, dir, &dentry->d_name, d_inode(dentry));
3286 92 : if (!retval)
3287 92 : ext4_fc_track_unlink(handle, dentry);
3288 : #ifdef CONFIG_UNICODE
3289 : /* VFS negative dentries are incompatible with Encoding and
3290 : * Case-insensitiveness. Eventually we'll want avoid
3291 : * invalidating the dentries here, alongside with returning the
3292 : * negative dentries at ext4_lookup(), when it is better
3293 : * supported by the VFS for the CI case.
3294 : */
3295 : if (IS_CASEFOLDED(dir))
3296 : d_invalidate(dentry);
3297 : #endif
3298 92 : if (handle)
3299 92 : ext4_journal_stop(handle);
3300 :
3301 0 : out_trace:
3302 92 : trace_ext4_unlink_exit(dentry, retval);
3303 92 : return retval;
3304 : }
3305 :
3306 0 : static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
3307 : struct dentry *dentry, const char *symname)
3308 : {
3309 0 : handle_t *handle;
3310 0 : struct inode *inode;
3311 0 : int err, len = strlen(symname);
3312 0 : int credits;
3313 0 : struct fscrypt_str disk_link;
3314 :
3315 0 : if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
3316 : return -EIO;
3317 :
3318 0 : err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,
3319 : &disk_link);
3320 0 : if (err)
3321 0 : return err;
3322 :
3323 0 : err = dquot_initialize(dir);
3324 0 : if (err)
3325 : return err;
3326 :
3327 0 : if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3328 : /*
3329 : * For non-fast symlinks, we just allocate inode and put it on
3330 : * orphan list in the first transaction => we need bitmap,
3331 : * group descriptor, sb, inode block, quota blocks, and
3332 : * possibly selinux xattr blocks.
3333 : */
3334 : credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
3335 : EXT4_XATTR_TRANS_BLOCKS;
3336 : } else {
3337 : /*
3338 : * Fast symlink. We have to add entry to directory
3339 : * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
3340 : * allocate new inode (bitmap, group descriptor, inode block,
3341 : * quota blocks, sb is already counted in previous macros).
3342 : */
3343 0 : credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3344 0 : EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
3345 : }
3346 :
3347 0 : inode = ext4_new_inode_start_handle(mnt_userns, dir, S_IFLNK|S_IRWXUGO,
3348 : &dentry->d_name, 0, NULL,
3349 : EXT4_HT_DIR, credits);
3350 0 : handle = ext4_journal_current_handle();
3351 0 : if (IS_ERR(inode)) {
3352 0 : if (handle)
3353 0 : ext4_journal_stop(handle);
3354 0 : return PTR_ERR(inode);
3355 : }
3356 :
3357 0 : if (IS_ENCRYPTED(inode)) {
3358 0 : err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
3359 0 : if (err)
3360 0 : goto err_drop_inode;
3361 : inode->i_op = &ext4_encrypted_symlink_inode_operations;
3362 : }
3363 :
3364 0 : if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
3365 0 : if (!IS_ENCRYPTED(inode))
3366 0 : inode->i_op = &ext4_symlink_inode_operations;
3367 0 : inode_nohighmem(inode);
3368 0 : ext4_set_aops(inode);
3369 : /*
3370 : * We cannot call page_symlink() with transaction started
3371 : * because it calls into ext4_write_begin() which can wait
3372 : * for transaction commit if we are running out of space
3373 : * and thus we deadlock. So we have to stop transaction now
3374 : * and restart it when symlink contents is written.
3375 : *
3376 : * To keep fs consistent in case of crash, we have to put inode
3377 : * to orphan list in the mean time.
3378 : */
3379 0 : drop_nlink(inode);
3380 0 : err = ext4_orphan_add(handle, inode);
3381 0 : if (handle)
3382 0 : ext4_journal_stop(handle);
3383 0 : handle = NULL;
3384 0 : if (err)
3385 0 : goto err_drop_inode;
3386 0 : err = __page_symlink(inode, disk_link.name, disk_link.len, 1);
3387 0 : if (err)
3388 0 : goto err_drop_inode;
3389 : /*
3390 : * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
3391 : * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
3392 : */
3393 0 : handle = ext4_journal_start(dir, EXT4_HT_DIR,
3394 : EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3395 : EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
3396 0 : if (IS_ERR(handle)) {
3397 0 : err = PTR_ERR(handle);
3398 0 : handle = NULL;
3399 0 : goto err_drop_inode;
3400 : }
3401 0 : set_nlink(inode, 1);
3402 0 : err = ext4_orphan_del(handle, inode);
3403 0 : if (err)
3404 0 : goto err_drop_inode;
3405 : } else {
3406 : /* clear the extent format for fast symlink */
3407 0 : ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
3408 0 : if (!IS_ENCRYPTED(inode)) {
3409 0 : inode->i_op = &ext4_fast_symlink_inode_operations;
3410 0 : inode->i_link = (char *)&EXT4_I(inode)->i_data;
3411 : }
3412 0 : memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name,
3413 : disk_link.len);
3414 0 : inode->i_size = disk_link.len - 1;
3415 : }
3416 0 : EXT4_I(inode)->i_disksize = inode->i_size;
3417 0 : err = ext4_add_nondir(handle, dentry, &inode);
3418 0 : if (handle)
3419 0 : ext4_journal_stop(handle);
3420 0 : if (inode)
3421 0 : iput(inode);
3422 0 : goto out_free_encrypted_link;
3423 :
3424 0 : err_drop_inode:
3425 0 : if (handle)
3426 0 : ext4_journal_stop(handle);
3427 0 : clear_nlink(inode);
3428 0 : unlock_new_inode(inode);
3429 0 : iput(inode);
3430 : out_free_encrypted_link:
3431 : if (disk_link.name != (unsigned char *)symname)
3432 : kfree(disk_link.name);
3433 : return err;
3434 : }
3435 :
3436 0 : int __ext4_link(struct inode *dir, struct inode *inode, struct dentry *dentry)
3437 : {
3438 0 : handle_t *handle;
3439 0 : int err, retries = 0;
3440 0 : retry:
3441 0 : handle = ext4_journal_start(dir, EXT4_HT_DIR,
3442 : (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
3443 : EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
3444 0 : if (IS_ERR(handle))
3445 0 : return PTR_ERR(handle);
3446 :
3447 0 : if (IS_DIRSYNC(dir))
3448 0 : ext4_handle_sync(handle);
3449 :
3450 0 : inode->i_ctime = current_time(inode);
3451 0 : ext4_inc_count(inode);
3452 0 : ihold(inode);
3453 :
3454 0 : err = ext4_add_entry(handle, dentry, inode);
3455 0 : if (!err) {
3456 0 : err = ext4_mark_inode_dirty(handle, inode);
3457 : /* this can happen only for tmpfile being
3458 : * linked the first time
3459 : */
3460 0 : if (inode->i_nlink == 1)
3461 0 : ext4_orphan_del(handle, inode);
3462 0 : d_instantiate(dentry, inode);
3463 0 : ext4_fc_track_link(handle, dentry);
3464 : } else {
3465 0 : drop_nlink(inode);
3466 0 : iput(inode);
3467 : }
3468 0 : ext4_journal_stop(handle);
3469 0 : if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
3470 0 : goto retry;
3471 : return err;
3472 : }
3473 :
3474 0 : static int ext4_link(struct dentry *old_dentry,
3475 : struct inode *dir, struct dentry *dentry)
3476 : {
3477 0 : struct inode *inode = d_inode(old_dentry);
3478 0 : int err;
3479 :
3480 0 : if (inode->i_nlink >= EXT4_LINK_MAX)
3481 : return -EMLINK;
3482 :
3483 0 : err = fscrypt_prepare_link(old_dentry, dir, dentry);
3484 0 : if (err)
3485 : return err;
3486 :
3487 0 : if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) &&
3488 0 : (!projid_eq(EXT4_I(dir)->i_projid,
3489 0 : EXT4_I(old_dentry->d_inode)->i_projid)))
3490 : return -EXDEV;
3491 :
3492 0 : err = dquot_initialize(dir);
3493 0 : if (err)
3494 : return err;
3495 0 : return __ext4_link(dir, inode, dentry);
3496 : }
3497 :
3498 : /*
3499 : * Try to find buffer head where contains the parent block.
3500 : * It should be the inode block if it is inlined or the 1st block
3501 : * if it is a normal dir.
3502 : */
3503 0 : static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
3504 : struct inode *inode,
3505 : int *retval,
3506 : struct ext4_dir_entry_2 **parent_de,
3507 : int *inlined)
3508 : {
3509 0 : struct buffer_head *bh;
3510 :
3511 0 : if (!ext4_has_inline_data(inode)) {
3512 : /* The first directory block must not be a hole, so
3513 : * treat it as DIRENT_HTREE
3514 : */
3515 0 : bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE);
3516 0 : if (IS_ERR(bh)) {
3517 0 : *retval = PTR_ERR(bh);
3518 0 : return NULL;
3519 : }
3520 0 : *parent_de = ext4_next_entry(
3521 0 : (struct ext4_dir_entry_2 *)bh->b_data,
3522 0 : inode->i_sb->s_blocksize);
3523 0 : return bh;
3524 : }
3525 :
3526 0 : *inlined = 1;
3527 0 : return ext4_get_first_inline_block(inode, parent_de, retval);
3528 : }
3529 :
3530 : struct ext4_renament {
3531 : struct inode *dir;
3532 : struct dentry *dentry;
3533 : struct inode *inode;
3534 : bool is_dir;
3535 : int dir_nlink_delta;
3536 :
3537 : /* entry for "dentry" */
3538 : struct buffer_head *bh;
3539 : struct ext4_dir_entry_2 *de;
3540 : int inlined;
3541 :
3542 : /* entry for ".." in inode if it's a directory */
3543 : struct buffer_head *dir_bh;
3544 : struct ext4_dir_entry_2 *parent_de;
3545 : int dir_inlined;
3546 : };
3547 :
3548 0 : static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
3549 : {
3550 0 : int retval;
3551 :
3552 0 : ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
3553 : &retval, &ent->parent_de,
3554 : &ent->dir_inlined);
3555 0 : if (!ent->dir_bh)
3556 0 : return retval;
3557 0 : if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
3558 : return -EFSCORRUPTED;
3559 0 : BUFFER_TRACE(ent->dir_bh, "get_write_access");
3560 0 : return ext4_journal_get_write_access(handle, ent->dir_bh);
3561 : }
3562 :
3563 0 : static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
3564 : unsigned dir_ino)
3565 : {
3566 0 : int retval;
3567 :
3568 0 : ent->parent_de->inode = cpu_to_le32(dir_ino);
3569 0 : BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
3570 0 : if (!ent->dir_inlined) {
3571 0 : if (is_dx(ent->inode)) {
3572 0 : retval = ext4_handle_dirty_dx_node(handle,
3573 : ent->inode,
3574 : ent->dir_bh);
3575 : } else {
3576 0 : retval = ext4_handle_dirty_dirblock(handle, ent->inode,
3577 : ent->dir_bh);
3578 : }
3579 : } else {
3580 0 : retval = ext4_mark_inode_dirty(handle, ent->inode);
3581 : }
3582 0 : if (retval) {
3583 0 : ext4_std_error(ent->dir->i_sb, retval);
3584 0 : return retval;
3585 : }
3586 : return 0;
3587 : }
3588 :
3589 30 : static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
3590 : unsigned ino, unsigned file_type)
3591 : {
3592 30 : int retval, retval2;
3593 :
3594 30 : BUFFER_TRACE(ent->bh, "get write access");
3595 30 : retval = ext4_journal_get_write_access(handle, ent->bh);
3596 30 : if (retval)
3597 : return retval;
3598 30 : ent->de->inode = cpu_to_le32(ino);
3599 30 : if (ext4_has_feature_filetype(ent->dir->i_sb))
3600 30 : ent->de->file_type = file_type;
3601 30 : inode_inc_iversion(ent->dir);
3602 60 : ent->dir->i_ctime = ent->dir->i_mtime =
3603 30 : current_time(ent->dir);
3604 30 : retval = ext4_mark_inode_dirty(handle, ent->dir);
3605 30 : BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
3606 30 : if (!ent->inlined) {
3607 30 : retval2 = ext4_handle_dirty_dirblock(handle, ent->dir, ent->bh);
3608 30 : if (unlikely(retval2)) {
3609 0 : ext4_std_error(ent->dir->i_sb, retval2);
3610 0 : return retval2;
3611 : }
3612 : }
3613 : return retval;
3614 : }
3615 :
3616 0 : static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
3617 : const struct qstr *d_name)
3618 : {
3619 0 : int retval = -ENOENT;
3620 0 : struct buffer_head *bh;
3621 0 : struct ext4_dir_entry_2 *de;
3622 :
3623 0 : bh = ext4_find_entry(dir, d_name, &de, NULL);
3624 0 : if (IS_ERR(bh))
3625 0 : return PTR_ERR(bh);
3626 0 : if (bh) {
3627 0 : retval = ext4_delete_entry(handle, dir, de, bh);
3628 0 : brelse(bh);
3629 : }
3630 : return retval;
3631 : }
3632 :
3633 101 : static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent,
3634 : int force_reread)
3635 : {
3636 101 : int retval;
3637 : /*
3638 : * ent->de could have moved from under us during htree split, so make
3639 : * sure that we are deleting the right entry. We might also be pointing
3640 : * to a stale entry in the unused part of ent->bh so just checking inum
3641 : * and the name isn't enough.
3642 : */
3643 101 : if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
3644 101 : ent->de->name_len != ent->dentry->d_name.len ||
3645 101 : strncmp(ent->de->name, ent->dentry->d_name.name,
3646 101 : ent->de->name_len) ||
3647 : force_reread) {
3648 0 : retval = ext4_find_delete_entry(handle, ent->dir,
3649 0 : &ent->dentry->d_name);
3650 : } else {
3651 101 : retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
3652 101 : if (retval == -ENOENT) {
3653 0 : retval = ext4_find_delete_entry(handle, ent->dir,
3654 0 : &ent->dentry->d_name);
3655 : }
3656 : }
3657 :
3658 101 : if (retval) {
3659 0 : ext4_warning_inode(ent->dir,
3660 : "Deleting old file: nlink %d, error=%d",
3661 : ent->dir->i_nlink, retval);
3662 : }
3663 101 : }
3664 :
3665 0 : static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
3666 : {
3667 0 : if (ent->dir_nlink_delta) {
3668 0 : if (ent->dir_nlink_delta == -1)
3669 0 : ext4_dec_count(ent->dir);
3670 : else
3671 0 : ext4_inc_count(ent->dir);
3672 0 : ext4_mark_inode_dirty(handle, ent->dir);
3673 : }
3674 0 : }
3675 :
3676 0 : static struct inode *ext4_whiteout_for_rename(struct user_namespace *mnt_userns,
3677 : struct ext4_renament *ent,
3678 : int credits, handle_t **h)
3679 : {
3680 0 : struct inode *wh;
3681 0 : handle_t *handle;
3682 0 : int retries = 0;
3683 :
3684 : /*
3685 : * for inode block, sb block, group summaries,
3686 : * and inode bitmap
3687 : */
3688 0 : credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
3689 : EXT4_XATTR_TRANS_BLOCKS + 4);
3690 0 : retry:
3691 0 : wh = ext4_new_inode_start_handle(mnt_userns, ent->dir,
3692 : S_IFCHR | WHITEOUT_MODE,
3693 : &ent->dentry->d_name, 0, NULL,
3694 : EXT4_HT_DIR, credits);
3695 :
3696 0 : handle = ext4_journal_current_handle();
3697 0 : if (IS_ERR(wh)) {
3698 0 : if (handle)
3699 0 : ext4_journal_stop(handle);
3700 0 : if (PTR_ERR(wh) == -ENOSPC &&
3701 0 : ext4_should_retry_alloc(ent->dir->i_sb, &retries))
3702 0 : goto retry;
3703 : } else {
3704 0 : *h = handle;
3705 0 : init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);
3706 0 : wh->i_op = &ext4_special_inode_operations;
3707 : }
3708 0 : return wh;
3709 : }
3710 :
3711 : /*
3712 : * Anybody can rename anything with this: the permission checks are left to the
3713 : * higher-level routines.
3714 : *
3715 : * n.b. old_{dentry,inode) refers to the source dentry/inode
3716 : * while new_{dentry,inode) refers to the destination dentry/inode
3717 : * This comes from rename(const char *oldpath, const char *newpath)
3718 : */
3719 101 : static int ext4_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
3720 : struct dentry *old_dentry, struct inode *new_dir,
3721 : struct dentry *new_dentry, unsigned int flags)
3722 : {
3723 101 : handle_t *handle = NULL;
3724 101 : struct ext4_renament old = {
3725 : .dir = old_dir,
3726 : .dentry = old_dentry,
3727 101 : .inode = d_inode(old_dentry),
3728 : };
3729 101 : struct ext4_renament new = {
3730 : .dir = new_dir,
3731 : .dentry = new_dentry,
3732 101 : .inode = d_inode(new_dentry),
3733 : };
3734 101 : int force_reread;
3735 101 : int retval;
3736 101 : struct inode *whiteout = NULL;
3737 101 : int credits;
3738 101 : u8 old_file_type;
3739 :
3740 101 : if (new.inode && new.inode->i_nlink == 0) {
3741 0 : EXT4_ERROR_INODE(new.inode,
3742 : "target of rename is already freed");
3743 0 : return -EFSCORRUPTED;
3744 : }
3745 :
3746 101 : if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) &&
3747 0 : (!projid_eq(EXT4_I(new_dir)->i_projid,
3748 0 : EXT4_I(old_dentry->d_inode)->i_projid)))
3749 : return -EXDEV;
3750 :
3751 101 : retval = dquot_initialize(old.dir);
3752 101 : if (retval)
3753 : return retval;
3754 101 : retval = dquot_initialize(new.dir);
3755 101 : if (retval)
3756 : return retval;
3757 :
3758 : /* Initialize quotas before so that eventual writes go
3759 : * in separate transaction */
3760 101 : if (new.inode) {
3761 101 : retval = dquot_initialize(new.inode);
3762 : if (retval)
3763 : return retval;
3764 : }
3765 :
3766 101 : old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
3767 101 : if (IS_ERR(old.bh))
3768 0 : return PTR_ERR(old.bh);
3769 : /*
3770 : * Check for inode number is _not_ due to possible IO errors.
3771 : * We might rmdir the source, keep it as pwd of some process
3772 : * and merrily kill the link to whatever was created under the
3773 : * same name. Goodbye sticky bit ;-<
3774 : */
3775 101 : retval = -ENOENT;
3776 101 : if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3777 0 : goto end_rename;
3778 :
3779 101 : new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3780 : &new.de, &new.inlined);
3781 101 : if (IS_ERR(new.bh)) {
3782 0 : retval = PTR_ERR(new.bh);
3783 0 : new.bh = NULL;
3784 0 : goto end_rename;
3785 : }
3786 101 : if (new.bh) {
3787 30 : if (!new.inode) {
3788 0 : brelse(new.bh);
3789 0 : new.bh = NULL;
3790 : }
3791 : }
3792 101 : if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
3793 30 : ext4_alloc_da_blocks(old.inode);
3794 :
3795 101 : credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3796 101 : EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
3797 101 : if (!(flags & RENAME_WHITEOUT)) {
3798 101 : handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);
3799 101 : if (IS_ERR(handle)) {
3800 0 : retval = PTR_ERR(handle);
3801 0 : handle = NULL;
3802 0 : goto end_rename;
3803 : }
3804 : } else {
3805 0 : whiteout = ext4_whiteout_for_rename(mnt_userns, &old, credits, &handle);
3806 0 : if (IS_ERR(whiteout)) {
3807 0 : retval = PTR_ERR(whiteout);
3808 0 : whiteout = NULL;
3809 0 : goto end_rename;
3810 : }
3811 : }
3812 :
3813 101 : old_file_type = old.de->file_type;
3814 101 : if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3815 0 : ext4_handle_sync(handle);
3816 :
3817 101 : if (S_ISDIR(old.inode->i_mode)) {
3818 0 : if (new.inode) {
3819 0 : retval = -ENOTEMPTY;
3820 0 : if (!ext4_empty_dir(new.inode))
3821 0 : goto end_rename;
3822 : } else {
3823 0 : retval = -EMLINK;
3824 0 : if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
3825 0 : goto end_rename;
3826 : }
3827 0 : retval = ext4_rename_dir_prepare(handle, &old);
3828 0 : if (retval)
3829 0 : goto end_rename;
3830 : }
3831 : /*
3832 : * If we're renaming a file within an inline_data dir and adding or
3833 : * setting the new dirent causes a conversion from inline_data to
3834 : * extents/blockmap, we need to force the dirent delete code to
3835 : * re-read the directory, or else we end up trying to delete a dirent
3836 : * from what is now the extent tree root (or a block map).
3837 : */
3838 101 : force_reread = (new.dir->i_ino == old.dir->i_ino &&
3839 101 : ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA));
3840 :
3841 101 : if (whiteout) {
3842 : /*
3843 : * Do this before adding a new entry, so the old entry is sure
3844 : * to be still pointing to the valid old entry.
3845 : */
3846 0 : retval = ext4_setent(handle, &old, whiteout->i_ino,
3847 : EXT4_FT_CHRDEV);
3848 0 : if (retval)
3849 0 : goto end_rename;
3850 0 : retval = ext4_mark_inode_dirty(handle, whiteout);
3851 0 : if (unlikely(retval))
3852 0 : goto end_rename;
3853 : }
3854 101 : if (!new.bh) {
3855 71 : retval = ext4_add_entry(handle, new.dentry, old.inode);
3856 71 : if (retval)
3857 0 : goto end_rename;
3858 : } else {
3859 60 : retval = ext4_setent(handle, &new,
3860 30 : old.inode->i_ino, old_file_type);
3861 30 : if (retval)
3862 0 : goto end_rename;
3863 : }
3864 101 : if (force_reread)
3865 0 : force_reread = !ext4_test_inode_flag(new.dir,
3866 : EXT4_INODE_INLINE_DATA);
3867 :
3868 : /*
3869 : * Like most other Unix systems, set the ctime for inodes on a
3870 : * rename.
3871 : */
3872 101 : old.inode->i_ctime = current_time(old.inode);
3873 101 : retval = ext4_mark_inode_dirty(handle, old.inode);
3874 101 : if (unlikely(retval))
3875 0 : goto end_rename;
3876 :
3877 101 : if (!whiteout) {
3878 : /*
3879 : * ok, that's it
3880 : */
3881 101 : ext4_rename_delete(handle, &old, force_reread);
3882 : }
3883 :
3884 101 : if (new.inode) {
3885 30 : ext4_dec_count(new.inode);
3886 30 : new.inode->i_ctime = current_time(new.inode);
3887 : }
3888 101 : old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir);
3889 101 : ext4_update_dx_flag(old.dir);
3890 101 : if (old.dir_bh) {
3891 0 : retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3892 0 : if (retval)
3893 0 : goto end_rename;
3894 :
3895 0 : ext4_dec_count(old.dir);
3896 0 : if (new.inode) {
3897 : /* checked ext4_empty_dir above, can't have another
3898 : * parent, ext4_dec_count() won't work for many-linked
3899 : * dirs */
3900 0 : clear_nlink(new.inode);
3901 : } else {
3902 0 : ext4_inc_count(new.dir);
3903 0 : ext4_update_dx_flag(new.dir);
3904 0 : retval = ext4_mark_inode_dirty(handle, new.dir);
3905 0 : if (unlikely(retval))
3906 0 : goto end_rename;
3907 : }
3908 : }
3909 101 : retval = ext4_mark_inode_dirty(handle, old.dir);
3910 101 : if (unlikely(retval))
3911 0 : goto end_rename;
3912 :
3913 101 : if (S_ISDIR(old.inode->i_mode)) {
3914 : /*
3915 : * We disable fast commits here that's because the
3916 : * replay code is not yet capable of changing dot dot
3917 : * dirents in directories.
3918 : */
3919 0 : ext4_fc_mark_ineligible(old.inode->i_sb,
3920 : EXT4_FC_REASON_RENAME_DIR);
3921 : } else {
3922 101 : if (new.inode)
3923 30 : ext4_fc_track_unlink(handle, new.dentry);
3924 101 : __ext4_fc_track_link(handle, old.inode, new.dentry);
3925 101 : __ext4_fc_track_unlink(handle, old.inode, old.dentry);
3926 : }
3927 :
3928 101 : if (new.inode) {
3929 30 : retval = ext4_mark_inode_dirty(handle, new.inode);
3930 30 : if (unlikely(retval))
3931 0 : goto end_rename;
3932 30 : if (!new.inode->i_nlink)
3933 30 : ext4_orphan_add(handle, new.inode);
3934 : }
3935 : retval = 0;
3936 :
3937 101 : end_rename:
3938 101 : if (whiteout) {
3939 0 : if (retval) {
3940 0 : ext4_setent(handle, &old,
3941 0 : old.inode->i_ino, old_file_type);
3942 0 : drop_nlink(whiteout);
3943 : }
3944 0 : unlock_new_inode(whiteout);
3945 0 : iput(whiteout);
3946 :
3947 : }
3948 101 : brelse(old.dir_bh);
3949 101 : brelse(old.bh);
3950 101 : brelse(new.bh);
3951 101 : if (handle)
3952 101 : ext4_journal_stop(handle);
3953 : return retval;
3954 : }
3955 :
3956 0 : static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
3957 : struct inode *new_dir, struct dentry *new_dentry)
3958 : {
3959 0 : handle_t *handle = NULL;
3960 0 : struct ext4_renament old = {
3961 : .dir = old_dir,
3962 : .dentry = old_dentry,
3963 0 : .inode = d_inode(old_dentry),
3964 : };
3965 0 : struct ext4_renament new = {
3966 : .dir = new_dir,
3967 : .dentry = new_dentry,
3968 0 : .inode = d_inode(new_dentry),
3969 : };
3970 0 : u8 new_file_type;
3971 0 : int retval;
3972 0 : struct timespec64 ctime;
3973 :
3974 0 : if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&
3975 0 : !projid_eq(EXT4_I(new_dir)->i_projid,
3976 0 : EXT4_I(old_dentry->d_inode)->i_projid)) ||
3977 0 : (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) &&
3978 0 : !projid_eq(EXT4_I(old_dir)->i_projid,
3979 0 : EXT4_I(new_dentry->d_inode)->i_projid)))
3980 0 : return -EXDEV;
3981 :
3982 0 : retval = dquot_initialize(old.dir);
3983 0 : if (retval)
3984 : return retval;
3985 0 : retval = dquot_initialize(new.dir);
3986 0 : if (retval)
3987 : return retval;
3988 :
3989 0 : old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
3990 : &old.de, &old.inlined);
3991 0 : if (IS_ERR(old.bh))
3992 0 : return PTR_ERR(old.bh);
3993 : /*
3994 : * Check for inode number is _not_ due to possible IO errors.
3995 : * We might rmdir the source, keep it as pwd of some process
3996 : * and merrily kill the link to whatever was created under the
3997 : * same name. Goodbye sticky bit ;-<
3998 : */
3999 0 : retval = -ENOENT;
4000 0 : if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
4001 0 : goto end_rename;
4002 :
4003 0 : new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
4004 : &new.de, &new.inlined);
4005 0 : if (IS_ERR(new.bh)) {
4006 0 : retval = PTR_ERR(new.bh);
4007 0 : new.bh = NULL;
4008 0 : goto end_rename;
4009 : }
4010 :
4011 : /* RENAME_EXCHANGE case: old *and* new must both exist */
4012 0 : if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
4013 0 : goto end_rename;
4014 :
4015 0 : handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
4016 : (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
4017 : 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
4018 0 : if (IS_ERR(handle)) {
4019 0 : retval = PTR_ERR(handle);
4020 0 : handle = NULL;
4021 0 : goto end_rename;
4022 : }
4023 :
4024 0 : if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
4025 0 : ext4_handle_sync(handle);
4026 :
4027 0 : if (S_ISDIR(old.inode->i_mode)) {
4028 0 : old.is_dir = true;
4029 0 : retval = ext4_rename_dir_prepare(handle, &old);
4030 0 : if (retval)
4031 0 : goto end_rename;
4032 : }
4033 0 : if (S_ISDIR(new.inode->i_mode)) {
4034 0 : new.is_dir = true;
4035 0 : retval = ext4_rename_dir_prepare(handle, &new);
4036 0 : if (retval)
4037 0 : goto end_rename;
4038 : }
4039 :
4040 : /*
4041 : * Other than the special case of overwriting a directory, parents'
4042 : * nlink only needs to be modified if this is a cross directory rename.
4043 : */
4044 0 : if (old.dir != new.dir && old.is_dir != new.is_dir) {
4045 0 : old.dir_nlink_delta = old.is_dir ? -1 : 1;
4046 0 : new.dir_nlink_delta = -old.dir_nlink_delta;
4047 0 : retval = -EMLINK;
4048 0 : if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
4049 0 : (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
4050 0 : goto end_rename;
4051 : }
4052 :
4053 0 : new_file_type = new.de->file_type;
4054 0 : retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
4055 0 : if (retval)
4056 0 : goto end_rename;
4057 :
4058 0 : retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
4059 0 : if (retval)
4060 0 : goto end_rename;
4061 :
4062 : /*
4063 : * Like most other Unix systems, set the ctime for inodes on a
4064 : * rename.
4065 : */
4066 0 : ctime = current_time(old.inode);
4067 0 : old.inode->i_ctime = ctime;
4068 0 : new.inode->i_ctime = ctime;
4069 0 : retval = ext4_mark_inode_dirty(handle, old.inode);
4070 0 : if (unlikely(retval))
4071 0 : goto end_rename;
4072 0 : retval = ext4_mark_inode_dirty(handle, new.inode);
4073 0 : if (unlikely(retval))
4074 0 : goto end_rename;
4075 0 : ext4_fc_mark_ineligible(new.inode->i_sb,
4076 : EXT4_FC_REASON_CROSS_RENAME);
4077 0 : if (old.dir_bh) {
4078 0 : retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
4079 0 : if (retval)
4080 0 : goto end_rename;
4081 : }
4082 0 : if (new.dir_bh) {
4083 0 : retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
4084 0 : if (retval)
4085 0 : goto end_rename;
4086 : }
4087 0 : ext4_update_dir_count(handle, &old);
4088 0 : ext4_update_dir_count(handle, &new);
4089 0 : retval = 0;
4090 :
4091 0 : end_rename:
4092 0 : brelse(old.dir_bh);
4093 0 : brelse(new.dir_bh);
4094 0 : brelse(old.bh);
4095 0 : brelse(new.bh);
4096 0 : if (handle)
4097 0 : ext4_journal_stop(handle);
4098 : return retval;
4099 : }
4100 :
4101 101 : static int ext4_rename2(struct user_namespace *mnt_userns,
4102 : struct inode *old_dir, struct dentry *old_dentry,
4103 : struct inode *new_dir, struct dentry *new_dentry,
4104 : unsigned int flags)
4105 : {
4106 101 : int err;
4107 :
4108 101 : if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb))))
4109 : return -EIO;
4110 :
4111 101 : if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
4112 : return -EINVAL;
4113 :
4114 101 : err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
4115 : flags);
4116 101 : if (err)
4117 : return err;
4118 :
4119 101 : if (flags & RENAME_EXCHANGE) {
4120 0 : return ext4_cross_rename(old_dir, old_dentry,
4121 : new_dir, new_dentry);
4122 : }
4123 :
4124 101 : return ext4_rename(mnt_userns, old_dir, old_dentry, new_dir, new_dentry, flags);
4125 : }
4126 :
4127 : /*
4128 : * directories can handle most operations...
4129 : */
4130 : const struct inode_operations ext4_dir_inode_operations = {
4131 : .create = ext4_create,
4132 : .lookup = ext4_lookup,
4133 : .link = ext4_link,
4134 : .unlink = ext4_unlink,
4135 : .symlink = ext4_symlink,
4136 : .mkdir = ext4_mkdir,
4137 : .rmdir = ext4_rmdir,
4138 : .mknod = ext4_mknod,
4139 : .tmpfile = ext4_tmpfile,
4140 : .rename = ext4_rename2,
4141 : .setattr = ext4_setattr,
4142 : .getattr = ext4_getattr,
4143 : .listxattr = ext4_listxattr,
4144 : .get_acl = ext4_get_acl,
4145 : .set_acl = ext4_set_acl,
4146 : .fiemap = ext4_fiemap,
4147 : };
4148 :
4149 : const struct inode_operations ext4_special_inode_operations = {
4150 : .setattr = ext4_setattr,
4151 : .getattr = ext4_getattr,
4152 : .listxattr = ext4_listxattr,
4153 : .get_acl = ext4_get_acl,
4154 : .set_acl = ext4_set_acl,
4155 : };
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