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ext4: reduce contention on s_orphan_lock
[linux-2.6-block.git] / fs / ext4 / namei.c
CommitLineData
ac27a0ec 1/*
617ba13b 2 * linux/fs/ext4/namei.c
ac27a0ec
DK		 3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/namei.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * Big-endian to little-endian byte-swapping/bitmaps by
16 * David S. Miller (davem@caip.rutgers.edu), 1995
17 * Directory entry file type support and forward compatibility hooks
18 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
19 * Hash Tree Directory indexing (c)
20 * Daniel Phillips, 2001
21 * Hash Tree Directory indexing porting
22 * Christopher Li, 2002
23 * Hash Tree Directory indexing cleanup
24 * Theodore Ts'o, 2002
25 */
26
27#include <linux/fs.h>
28#include <linux/pagemap.h>
dab291af 29#include <linux/jbd2.h>
ac27a0ec 30#include <linux/time.h>
ac27a0ec
DK		 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>
3dcf5451
CH		 37#include "ext4.h"
38#include "ext4_jbd2.h"
ac27a0ec 39
ac27a0ec
DK		 40#include "xattr.h"
41#include "acl.h"
42
0562e0ba 43#include <trace/events/ext4.h>
ac27a0ec
DK		 44/*
45 * define how far ahead to read directories while searching them.
46 */
47#define NAMEI_RA_CHUNKS 2
48#define NAMEI_RA_BLOCKS 4
8c55e204 49#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
ac27a0ec 50
617ba13b 51static struct buffer_head *ext4_append(handle_t *handle,
ac27a0ec 52 struct inode *inode,
0f70b406 53 ext4_lblk_t *block)
ac27a0ec
DK		 54{
55 struct buffer_head *bh;
0f70b406 56 int err = 0;
ac27a0ec 57
df981d03
TT		 58 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
59 ((inode->i_size >> 10) >=
0f70b406
TT		 60 EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))
61 return ERR_PTR(-ENOSPC);
df981d03 62
ac27a0ec
DK		 63 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
64
0f70b406
TT		 65 bh = ext4_bread(handle, inode, *block, 1, &err);
66 if (!bh)
67 return ERR_PTR(err);
68 inode->i_size += inode->i_sb->s_blocksize;
69 EXT4_I(inode)->i_disksize = inode->i_size;
5d601255 70 BUFFER_TRACE(bh, "get_write_access");
0f70b406
TT		 71 err = ext4_journal_get_write_access(handle, bh);
72 if (err) {
73 brelse(bh);
74 ext4_std_error(inode->i_sb, err);
75 return ERR_PTR(err);
6d1ab10e 76 }
ac27a0ec
DK		 77 return bh;
78}
79
dc6982ff
TT		 80static int ext4_dx_csum_verify(struct inode *inode,
81 struct ext4_dir_entry *dirent);
82
83typedef enum {
84 EITHER, INDEX, DIRENT
85} dirblock_type_t;
86
87#define ext4_read_dirblock(inode, block, type) \
88 __ext4_read_dirblock((inode), (block), (type), __LINE__)
89
90static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
91 ext4_lblk_t block,
92 dirblock_type_t type,
93 unsigned int line)
94{
95 struct buffer_head *bh;
96 struct ext4_dir_entry *dirent;
97 int err = 0, is_dx_block = 0;
98
99 bh = ext4_bread(NULL, inode, block, 0, &err);
100 if (!bh) {
101 if (err == 0) {
102 ext4_error_inode(inode, __func__, line, block,
103 "Directory hole found");
104 return ERR_PTR(-EIO);
105 }
106 __ext4_warning(inode->i_sb, __func__, line,
107 "error reading directory block "
108 "(ino %lu, block %lu)", inode->i_ino,
109 (unsigned long) block);
110 return ERR_PTR(err);
111 }
112 dirent = (struct ext4_dir_entry *) bh->b_data;
113 /* Determine whether or not we have an index block */
114 if (is_dx(inode)) {
115 if (block == 0)
116 is_dx_block = 1;
117 else if (ext4_rec_len_from_disk(dirent->rec_len,
118 inode->i_sb->s_blocksize) ==
119 inode->i_sb->s_blocksize)
120 is_dx_block = 1;
121 }
122 if (!is_dx_block && type == INDEX) {
123 ext4_error_inode(inode, __func__, line, block,
124 "directory leaf block found instead of index block");
125 return ERR_PTR(-EIO);
126 }
127 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
128 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) ||
129 buffer_verified(bh))
130 return bh;
131
132 /*
133 * An empty leaf block can get mistaken for a index block; for
134 * this reason, we can only check the index checksum when the
135 * caller is sure it should be an index block.
136 */
137 if (is_dx_block && type == INDEX) {
138 if (ext4_dx_csum_verify(inode, dirent))
139 set_buffer_verified(bh);
140 else {
141 ext4_error_inode(inode, __func__, line, block,
142 "Directory index failed checksum");
a871611b 143 brelse(bh);
dc6982ff 144 return ERR_PTR(-EIO);
a871611b 145 }
ac27a0ec 146 }
dc6982ff
TT		 147 if (!is_dx_block) {
148 if (ext4_dirent_csum_verify(inode, dirent))
149 set_buffer_verified(bh);
150 else {
151 ext4_error_inode(inode, __func__, line, block,
152 "Directory block failed checksum");
153 brelse(bh);
154 return ERR_PTR(-EIO);
155 }
6d1ab10e 156 }
ac27a0ec
DK		 157 return bh;
158}
159
160#ifndef assert
161#define assert(test) J_ASSERT(test)
162#endif
163
ac27a0ec
DK		 164#ifdef DX_DEBUG
165#define dxtrace(command) command
166#else
167#define dxtrace(command)
168#endif
169
170struct fake_dirent
171{
172 __le32 inode;
173 __le16 rec_len;
174 u8 name_len;
175 u8 file_type;
176};
177
178struct dx_countlimit
179{
180 __le16 limit;
181 __le16 count;
182};
183
184struct dx_entry
185{
186 __le32 hash;
187 __le32 block;
188};
189
190/*
191 * dx_root_info is laid out so that if it should somehow get overlaid by a
192 * dirent the two low bits of the hash version will be zero. Therefore, the
193 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
194 */
195
196struct dx_root
197{
198 struct fake_dirent dot;
199 char dot_name[4];
200 struct fake_dirent dotdot;
201 char dotdot_name[4];
202 struct dx_root_info
203 {
204 __le32 reserved_zero;
205 u8 hash_version;
206 u8 info_length; /* 8 */
207 u8 indirect_levels;
208 u8 unused_flags;
209 }
210 info;
211 struct dx_entry entries[0];
212};
213
214struct dx_node
215{
216 struct fake_dirent fake;
217 struct dx_entry entries[0];
218};
219
220
221struct dx_frame
222{
223 struct buffer_head *bh;
224 struct dx_entry *entries;
225 struct dx_entry *at;
226};
227
228struct dx_map_entry
229{
230 u32 hash;
ef2b02d3
ES		 231 u16 offs;
232 u16 size;
ac27a0ec
DK		 233};
234
e6153918
DW		 235/*
236 * This goes at the end of each htree block.
237 */
238struct dx_tail {
239 u32 dt_reserved;
240 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
241};
242
725d26d3
AK		 243static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
244static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
af5bc92d
TT		 245static inline unsigned dx_get_hash(struct dx_entry *entry);
246static void dx_set_hash(struct dx_entry *entry, unsigned value);
247static unsigned dx_get_count(struct dx_entry *entries);
248static unsigned dx_get_limit(struct dx_entry *entries);
249static void dx_set_count(struct dx_entry *entries, unsigned value);
250static void dx_set_limit(struct dx_entry *entries, unsigned value);
251static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
252static unsigned dx_node_limit(struct inode *dir);
f702ba0f 253static struct dx_frame *dx_probe(const struct qstr *d_name,
ac27a0ec
DK		 254 struct inode *dir,
255 struct dx_hash_info *hinfo,
256 struct dx_frame *frame,
257 int *err);
af5bc92d 258static void dx_release(struct dx_frame *frames);
8bad4597 259static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
af5bc92d 260 struct dx_hash_info *hinfo, struct dx_map_entry map[]);
ac27a0ec 261static void dx_sort_map(struct dx_map_entry *map, unsigned count);
af5bc92d 262static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
3d0518f4 263 struct dx_map_entry *offsets, int count, unsigned blocksize);
8bad4597 264static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
725d26d3
AK		 265static void dx_insert_block(struct dx_frame *frame,
266 u32 hash, ext4_lblk_t block);
617ba13b 267static int ext4_htree_next_block(struct inode *dir, __u32 hash,
ac27a0ec
DK		 268 struct dx_frame *frame,
269 struct dx_frame *frames,
270 __u32 *start_hash);
f702ba0f
TT		 271static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
272 const struct qstr *d_name,
273 struct ext4_dir_entry_2 **res_dir,
274 int *err);
617ba13b 275static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
ac27a0ec
DK		 276 struct inode *inode);
277
dbe89444 278/* checksumming functions */
3c47d541
TM		 279void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
280 unsigned int blocksize)
b0336e8d
DW		 281{
282 memset(t, 0, sizeof(struct ext4_dir_entry_tail));
283 t->det_rec_len = ext4_rec_len_to_disk(
284 sizeof(struct ext4_dir_entry_tail), blocksize);
285 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
286}
287
288/* Walk through a dirent block to find a checksum "dirent" at the tail */
289static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
290 struct ext4_dir_entry *de)
291{
292 struct ext4_dir_entry_tail *t;
293
294#ifdef PARANOID
295 struct ext4_dir_entry *d, *top;
296
297 d = de;
298 top = (struct ext4_dir_entry *)(((void *)de) +
299 (EXT4_BLOCK_SIZE(inode->i_sb) -
300 sizeof(struct ext4_dir_entry_tail)));
301 while (d < top && d->rec_len)
302 d = (struct ext4_dir_entry *)(((void *)d) +
303 le16_to_cpu(d->rec_len));
304
305 if (d != top)
306 return NULL;
307
308 t = (struct ext4_dir_entry_tail *)d;
309#else
310 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
311#endif
312
313 if (t->det_reserved_zero1 ||
314 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
315 t->det_reserved_zero2 ||
316 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
317 return NULL;
318
319 return t;
320}
321
322static __le32 ext4_dirent_csum(struct inode *inode,
323 struct ext4_dir_entry *dirent, int size)
324{
325 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
326 struct ext4_inode_info *ei = EXT4_I(inode);
327 __u32 csum;
328
329 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
330 return cpu_to_le32(csum);
331}
332
dffe9d8d
TT		 333static void warn_no_space_for_csum(struct inode *inode)
334{
335 ext4_warning(inode->i_sb, "no space in directory inode %lu leaf for "
336 "checksum. Please run e2fsck -D.", inode->i_ino);
337}
338
b0336e8d
DW		 339int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
340{
341 struct ext4_dir_entry_tail *t;
342
343 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
344 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
345 return 1;
346
347 t = get_dirent_tail(inode, dirent);
348 if (!t) {
dffe9d8d 349 warn_no_space_for_csum(inode);
b0336e8d
DW		 350 return 0;
351 }
352
353 if (t->det_checksum != ext4_dirent_csum(inode, dirent,
354 (void *)t - (void *)dirent))
355 return 0;
356
357 return 1;
358}
359
360static void ext4_dirent_csum_set(struct inode *inode,
361 struct ext4_dir_entry *dirent)
362{
363 struct ext4_dir_entry_tail *t;
364
365 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
366 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
367 return;
368
369 t = get_dirent_tail(inode, dirent);
370 if (!t) {
dffe9d8d 371 warn_no_space_for_csum(inode);
b0336e8d
DW		 372 return;
373 }
374
375 t->det_checksum = ext4_dirent_csum(inode, dirent,
376 (void *)t - (void *)dirent);
377}
378
3c47d541
TM		 379int ext4_handle_dirty_dirent_node(handle_t *handle,
380 struct inode *inode,
381 struct buffer_head *bh)
b0336e8d
DW		 382{
383 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
384 return ext4_handle_dirty_metadata(handle, inode, bh);
385}
386
dbe89444
DW		 387static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
388 struct ext4_dir_entry *dirent,
389 int *offset)
390{
391 struct ext4_dir_entry *dp;
392 struct dx_root_info *root;
393 int count_offset;
394
395 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
396 count_offset = 8;
397 else if (le16_to_cpu(dirent->rec_len) == 12) {
398 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
399 if (le16_to_cpu(dp->rec_len) !=
400 EXT4_BLOCK_SIZE(inode->i_sb) - 12)
401 return NULL;
402 root = (struct dx_root_info *)(((void *)dp + 12));
403 if (root->reserved_zero ||
404 root->info_length != sizeof(struct dx_root_info))
405 return NULL;
406 count_offset = 32;
407 } else
408 return NULL;
409
410 if (offset)
411 *offset = count_offset;
412 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
413}
414
415static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
416 int count_offset, int count, struct dx_tail *t)
417{
418 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
419 struct ext4_inode_info *ei = EXT4_I(inode);
d6a77105
TT		 420 __u32 csum;
421 __le32 save_csum;
dbe89444
DW		 422 int size;
423
424 size = count_offset + (count * sizeof(struct dx_entry));
d6a77105 425 save_csum = t->dt_checksum;
dbe89444
DW		 426 t->dt_checksum = 0;
427 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
428 csum = ext4_chksum(sbi, csum, (__u8 *)t, sizeof(struct dx_tail));
d6a77105 429 t->dt_checksum = save_csum;
dbe89444
DW		 430
431 return cpu_to_le32(csum);
432}
433
434static int ext4_dx_csum_verify(struct inode *inode,
435 struct ext4_dir_entry *dirent)
436{
437 struct dx_countlimit *c;
438 struct dx_tail *t;
439 int count_offset, limit, count;
440
441 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
442 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
443 return 1;
444
445 c = get_dx_countlimit(inode, dirent, &count_offset);
446 if (!c) {
447 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
448 return 1;
449 }
450 limit = le16_to_cpu(c->limit);
451 count = le16_to_cpu(c->count);
452 if (count_offset + (limit * sizeof(struct dx_entry)) >
453 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
dffe9d8d 454 warn_no_space_for_csum(inode);
dbe89444
DW		 455 return 1;
456 }
457 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
458
459 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
460 count, t))
461 return 0;
462 return 1;
463}
464
465static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
466{
467 struct dx_countlimit *c;
468 struct dx_tail *t;
469 int count_offset, limit, count;
470
471 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
472 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
473 return;
474
475 c = get_dx_countlimit(inode, dirent, &count_offset);
476 if (!c) {
477 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
478 return;
479 }
480 limit = le16_to_cpu(c->limit);
481 count = le16_to_cpu(c->count);
482 if (count_offset + (limit * sizeof(struct dx_entry)) >
483 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
dffe9d8d 484 warn_no_space_for_csum(inode);
dbe89444
DW		 485 return;
486 }
487 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
488
489 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
490}
491
492static inline int ext4_handle_dirty_dx_node(handle_t *handle,
493 struct inode *inode,
494 struct buffer_head *bh)
495{
496 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
497 return ext4_handle_dirty_metadata(handle, inode, bh);
498}
499
f795e140
LZ		 500/*
501 * p is at least 6 bytes before the end of page
502 */
503static inline struct ext4_dir_entry_2 *
3d0518f4 504ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
f795e140
LZ		 505{
506 return (struct ext4_dir_entry_2 *)((char *)p +
3d0518f4 507 ext4_rec_len_from_disk(p->rec_len, blocksize));
f795e140
LZ		 508}
509
ac27a0ec
DK		 510/*
511 * Future: use high four bits of block for coalesce-on-delete flags
512 * Mask them off for now.
513 */
514
725d26d3 515static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
ac27a0ec
DK		 516{
517 return le32_to_cpu(entry->block) & 0x00ffffff;
518}
519
725d26d3 520static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
ac27a0ec
DK		 521{
522 entry->block = cpu_to_le32(value);
523}
524
af5bc92d 525static inline unsigned dx_get_hash(struct dx_entry *entry)
ac27a0ec
DK		 526{
527 return le32_to_cpu(entry->hash);
528}
529
af5bc92d 530static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
ac27a0ec
DK		 531{
532 entry->hash = cpu_to_le32(value);
533}
534
af5bc92d 535static inline unsigned dx_get_count(struct dx_entry *entries)
ac27a0ec
DK		 536{
537 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
538}
539
af5bc92d 540static inline unsigned dx_get_limit(struct dx_entry *entries)
ac27a0ec
DK		 541{
542 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
543}
544
af5bc92d 545static inline void dx_set_count(struct dx_entry *entries, unsigned value)
ac27a0ec
DK		 546{
547 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
548}
549
af5bc92d 550static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
ac27a0ec
DK		 551{
552 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
553}
554
af5bc92d 555static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
ac27a0ec 556{
617ba13b
MC		 557 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
558 EXT4_DIR_REC_LEN(2) - infosize;
dbe89444
DW		 559
560 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
561 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
562 entry_space -= sizeof(struct dx_tail);
d9c769b7 563 return entry_space / sizeof(struct dx_entry);
ac27a0ec
DK		 564}
565
af5bc92d 566static inline unsigned dx_node_limit(struct inode *dir)
ac27a0ec 567{
617ba13b 568 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
dbe89444
DW		 569
570 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
571 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
572 entry_space -= sizeof(struct dx_tail);
d9c769b7 573 return entry_space / sizeof(struct dx_entry);
ac27a0ec
DK		 574}
575
576/*
577 * Debug
578 */
579#ifdef DX_DEBUG
4776004f 580static void dx_show_index(char * label, struct dx_entry *entries)
ac27a0ec 581{
63f57933 582 int i, n = dx_get_count (entries);
4776004f 583 printk(KERN_DEBUG "%s index ", label);
63f57933 584 for (i = 0; i < n; i++) {
4776004f 585 printk("%x->%lu ", i ? dx_get_hash(entries + i) :
725d26d3 586 0, (unsigned long)dx_get_block(entries + i));
63f57933
AM		 587 }
588 printk("\n");
ac27a0ec
DK		 589}
590
591struct stats
592{
593 unsigned names;
594 unsigned space;
595 unsigned bcount;
596};
597
617ba13b 598static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
ac27a0ec
DK		 599 int size, int show_names)
600{
601 unsigned names = 0, space = 0;
602 char *base = (char *) de;
603 struct dx_hash_info h = *hinfo;
604
605 printk("names: ");
606 while ((char *) de < base + size)
607 {
608 if (de->inode)
609 {
610 if (show_names)
611 {
612 int len = de->name_len;
613 char *name = de->name;
614 while (len--) printk("%c", *name++);
617ba13b 615 ext4fs_dirhash(de->name, de->name_len, &h);
ac27a0ec 616 printk(":%x.%u ", h.hash,
265c6a0f 617 (unsigned) ((char *) de - base));
ac27a0ec 618 }
617ba13b 619 space += EXT4_DIR_REC_LEN(de->name_len);
ac27a0ec
DK		 620 names++;
621 }
3d0518f4 622 de = ext4_next_entry(de, size);
ac27a0ec
DK		 623 }
624 printk("(%i)\n", names);
625 return (struct stats) { names, space, 1 };
626}
627
628struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
629 struct dx_entry *entries, int levels)
630{
631 unsigned blocksize = dir->i_sb->s_blocksize;
af5bc92d 632 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
ac27a0ec
DK		 633 unsigned bcount = 0;
634 struct buffer_head *bh;
635 int err;
636 printk("%i indexed blocks...\n", count);
637 for (i = 0; i < count; i++, entries++)
638 {
725d26d3
AK		 639 ext4_lblk_t block = dx_get_block(entries);
640 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
ac27a0ec
DK		 641 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
642 struct stats stats;
643 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
617ba13b 644 if (!(bh = ext4_bread (NULL,dir, block, 0,&err))) continue;
ac27a0ec
DK		 645 stats = levels?
646 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
617ba13b 647 dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
ac27a0ec
DK		 648 names += stats.names;
649 space += stats.space;
650 bcount += stats.bcount;
af5bc92d 651 brelse(bh);
ac27a0ec
DK		 652 }
653 if (bcount)
60e6679e 654 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
4776004f
TT		 655 levels ? "" : " ", names, space/bcount,
656 (space/bcount)*100/blocksize);
ac27a0ec
DK		 657 return (struct stats) { names, space, bcount};
658}
659#endif /* DX_DEBUG */
660
661/*
662 * Probe for a directory leaf block to search.
663 *
664 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
665 * error in the directory index, and the caller should fall back to
666 * searching the directory normally. The callers of dx_probe **MUST**
667 * check for this error code, and make sure it never gets reflected
668 * back to userspace.
669 */
670static struct dx_frame *
f702ba0f 671dx_probe(const struct qstr *d_name, struct inode *dir,
ac27a0ec
DK		 672 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
673{
674 unsigned count, indirect;
675 struct dx_entry *at, *entries, *p, *q, *m;
676 struct dx_root *root;
677 struct buffer_head *bh;
678 struct dx_frame *frame = frame_in;
679 u32 hash;
680
681 frame->bh = NULL;
dc6982ff
TT		 682 bh = ext4_read_dirblock(dir, 0, INDEX);
683 if (IS_ERR(bh)) {
684 *err = PTR_ERR(bh);
ac27a0ec 685 goto fail;
6d1ab10e 686 }
ac27a0ec
DK		 687 root = (struct dx_root *) bh->b_data;
688 if (root->info.hash_version != DX_HASH_TEA &&
689 root->info.hash_version != DX_HASH_HALF_MD4 &&
690 root->info.hash_version != DX_HASH_LEGACY) {
12062ddd 691 ext4_warning(dir->i_sb, "Unrecognised inode hash code %d",
ac27a0ec
DK		 692 root->info.hash_version);
693 brelse(bh);
694 *err = ERR_BAD_DX_DIR;
695 goto fail;
696 }
697 hinfo->hash_version = root->info.hash_version;
f99b2589
TT		 698 if (hinfo->hash_version <= DX_HASH_TEA)
699 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
617ba13b 700 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
f702ba0f
TT		 701 if (d_name)
702 ext4fs_dirhash(d_name->name, d_name->len, hinfo);
ac27a0ec
DK		 703 hash = hinfo->hash;
704
705 if (root->info.unused_flags & 1) {
12062ddd 706 ext4_warning(dir->i_sb, "Unimplemented inode hash flags: %#06x",
ac27a0ec
DK		 707 root->info.unused_flags);
708 brelse(bh);
709 *err = ERR_BAD_DX_DIR;
710 goto fail;
711 }
712
713 if ((indirect = root->info.indirect_levels) > 1) {
12062ddd 714 ext4_warning(dir->i_sb, "Unimplemented inode hash depth: %#06x",
ac27a0ec
DK		 715 root->info.indirect_levels);
716 brelse(bh);
717 *err = ERR_BAD_DX_DIR;
718 goto fail;
719 }
720
721 entries = (struct dx_entry *) (((char *)&root->info) +
722 root->info.info_length);
3d82abae
ES		 723
724 if (dx_get_limit(entries) != dx_root_limit(dir,
725 root->info.info_length)) {
12062ddd 726 ext4_warning(dir->i_sb, "dx entry: limit != root limit");
3d82abae
ES		 727 brelse(bh);
728 *err = ERR_BAD_DX_DIR;
729 goto fail;
730 }
731
af5bc92d 732 dxtrace(printk("Look up %x", hash));
ac27a0ec
DK		 733 while (1)
734 {
735 count = dx_get_count(entries);
3d82abae 736 if (!count || count > dx_get_limit(entries)) {
12062ddd 737 ext4_warning(dir->i_sb,
3d82abae
ES		 738 "dx entry: no count or count > limit");
739 brelse(bh);
740 *err = ERR_BAD_DX_DIR;
741 goto fail2;
742 }
743
ac27a0ec
DK		 744 p = entries + 1;
745 q = entries + count - 1;
746 while (p <= q)
747 {
748 m = p + (q - p)/2;
749 dxtrace(printk("."));
750 if (dx_get_hash(m) > hash)
751 q = m - 1;
752 else
753 p = m + 1;
754 }
755
756 if (0) // linear search cross check
757 {
758 unsigned n = count - 1;
759 at = entries;
760 while (n--)
761 {
762 dxtrace(printk(","));
763 if (dx_get_hash(++at) > hash)
764 {
765 at--;
766 break;
767 }
768 }
769 assert (at == p - 1);
770 }
771
772 at = p - 1;
773 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
774 frame->bh = bh;
775 frame->entries = entries;
776 frame->at = at;
777 if (!indirect--) return frame;
dc6982ff
TT		 778 bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
779 if (IS_ERR(bh)) {
780 *err = PTR_ERR(bh);
0ecaef06 781 goto fail2;
dbe89444 782 }
41be871f 783 entries = ((struct dx_node *) bh->b_data)->entries;
dbe89444 784
3d82abae 785 if (dx_get_limit(entries) != dx_node_limit (dir)) {
12062ddd 786 ext4_warning(dir->i_sb,
3d82abae
ES		 787 "dx entry: limit != node limit");
788 brelse(bh);
789 *err = ERR_BAD_DX_DIR;
790 goto fail2;
791 }
ac27a0ec 792 frame++;
3d82abae 793 frame->bh = NULL;
ac27a0ec
DK		 794 }
795fail2:
796 while (frame >= frame_in) {
797 brelse(frame->bh);
798 frame--;
799 }
800fail:
3d82abae 801 if (*err == ERR_BAD_DX_DIR)
12062ddd 802 ext4_warning(dir->i_sb,
9ee49302 803 "Corrupt dir inode %lu, running e2fsck is "
3d82abae 804 "recommended.", dir->i_ino);
ac27a0ec
DK		 805 return NULL;
806}
807
808static void dx_release (struct dx_frame *frames)
809{
810 if (frames[0].bh == NULL)
811 return;
812
813 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
814 brelse(frames[1].bh);
815 brelse(frames[0].bh);
816}
817
818/*
819 * This function increments the frame pointer to search the next leaf
820 * block, and reads in the necessary intervening nodes if the search
821 * should be necessary. Whether or not the search is necessary is
822 * controlled by the hash parameter. If the hash value is even, then
823 * the search is only continued if the next block starts with that
824 * hash value. This is used if we are searching for a specific file.
825 *
826 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
827 *
828 * This function returns 1 if the caller should continue to search,
829 * or 0 if it should not. If there is an error reading one of the
830 * index blocks, it will a negative error code.
831 *
832 * If start_hash is non-null, it will be filled in with the starting
833 * hash of the next page.
834 */
617ba13b 835static int ext4_htree_next_block(struct inode *dir, __u32 hash,
ac27a0ec
DK		 836 struct dx_frame *frame,
837 struct dx_frame *frames,
838 __u32 *start_hash)
839{
840 struct dx_frame *p;
841 struct buffer_head *bh;
dc6982ff 842 int num_frames = 0;
ac27a0ec
DK		 843 __u32 bhash;
844
845 p = frame;
846 /*
847 * Find the next leaf page by incrementing the frame pointer.
848 * If we run out of entries in the interior node, loop around and
849 * increment pointer in the parent node. When we break out of
850 * this loop, num_frames indicates the number of interior
851 * nodes need to be read.
852 */
853 while (1) {
854 if (++(p->at) < p->entries + dx_get_count(p->entries))
855 break;
856 if (p == frames)
857 return 0;
858 num_frames++;
859 p--;
860 }
861
862 /*
863 * If the hash is 1, then continue only if the next page has a
864 * continuation hash of any value. This is used for readdir
865 * handling. Otherwise, check to see if the hash matches the
866 * desired contiuation hash. If it doesn't, return since
867 * there's no point to read in the successive index pages.
868 */
869 bhash = dx_get_hash(p->at);
870 if (start_hash)
871 *start_hash = bhash;
872 if ((hash & 1) == 0) {
873 if ((bhash & ~1) != hash)
874 return 0;
875 }
876 /*
877 * If the hash is HASH_NB_ALWAYS, we always go to the next
878 * block so no check is necessary
879 */
880 while (num_frames--) {
dc6982ff
TT		 881 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);
882 if (IS_ERR(bh))
883 return PTR_ERR(bh);
ac27a0ec 884 p++;
af5bc92d 885 brelse(p->bh);
ac27a0ec
DK		 886 p->bh = bh;
887 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
888 }
889 return 1;
890}
891
892
ac27a0ec
DK		 893/*
894 * This function fills a red-black tree with information from a
895 * directory block. It returns the number directory entries loaded
896 * into the tree. If there is an error it is returned in err.
897 */
898static int htree_dirblock_to_tree(struct file *dir_file,
725d26d3 899 struct inode *dir, ext4_lblk_t block,
ac27a0ec
DK		 900 struct dx_hash_info *hinfo,
901 __u32 start_hash, __u32 start_minor_hash)
902{
903 struct buffer_head *bh;
617ba13b 904 struct ext4_dir_entry_2 *de, *top;
90b0a973 905 int err = 0, count = 0;
ac27a0ec 906
725d26d3
AK		 907 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
908 (unsigned long)block));
dc6982ff
TT		 909 bh = ext4_read_dirblock(dir, block, DIRENT);
910 if (IS_ERR(bh))
911 return PTR_ERR(bh);
b0336e8d 912
617ba13b
MC		 913 de = (struct ext4_dir_entry_2 *) bh->b_data;
914 top = (struct ext4_dir_entry_2 *) ((char *) de +
ac27a0ec 915 dir->i_sb->s_blocksize -
617ba13b 916 EXT4_DIR_REC_LEN(0));
3d0518f4 917 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
f7c21177 918 if (ext4_check_dir_entry(dir, NULL, de, bh,
226ba972 919 bh->b_data, bh->b_size,
cad3f007
TT		 920 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
921 + ((char *)de - bh->b_data))) {
64cb9273
AV		 922 /* silently ignore the rest of the block */
923 break;
e6c40211 924 }
617ba13b 925 ext4fs_dirhash(de->name, de->name_len, hinfo);
ac27a0ec
DK		 926 if ((hinfo->hash < start_hash) ||
927 ((hinfo->hash == start_hash) &&
928 (hinfo->minor_hash < start_minor_hash)))
929 continue;
930 if (de->inode == 0)
931 continue;
617ba13b 932 if ((err = ext4_htree_store_dirent(dir_file,
ac27a0ec
DK		 933 hinfo->hash, hinfo->minor_hash, de)) != 0) {
934 brelse(bh);
935 return err;
936 }
937 count++;
938 }
939 brelse(bh);
940 return count;
941}
942
943
944/*
945 * This function fills a red-black tree with information from a
946 * directory. We start scanning the directory in hash order, starting
947 * at start_hash and start_minor_hash.
948 *
949 * This function returns the number of entries inserted into the tree,
950 * or a negative error code.
951 */
617ba13b 952int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
ac27a0ec
DK		 953 __u32 start_minor_hash, __u32 *next_hash)
954{
955 struct dx_hash_info hinfo;
617ba13b 956 struct ext4_dir_entry_2 *de;
ac27a0ec
DK		 957 struct dx_frame frames[2], *frame;
958 struct inode *dir;
725d26d3 959 ext4_lblk_t block;
ac27a0ec 960 int count = 0;
725d26d3 961 int ret, err;
ac27a0ec
DK		 962 __u32 hashval;
963
60e6679e 964 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
4776004f 965 start_hash, start_minor_hash));
496ad9aa 966 dir = file_inode(dir_file);
12e9b892 967 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
617ba13b 968 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
f99b2589
TT		 969 if (hinfo.hash_version <= DX_HASH_TEA)
970 hinfo.hash_version +=
971 EXT4_SB(dir->i_sb)->s_hash_unsigned;
617ba13b 972 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
8af0f082
TM		 973 if (ext4_has_inline_data(dir)) {
974 int has_inline_data = 1;
975 count = htree_inlinedir_to_tree(dir_file, dir, 0,
976 &hinfo, start_hash,
977 start_minor_hash,
978 &has_inline_data);
979 if (has_inline_data) {
980 *next_hash = ~0;
981 return count;
982 }
983 }
ac27a0ec
DK		 984 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
985 start_hash, start_minor_hash);
986 *next_hash = ~0;
987 return count;
988 }
989 hinfo.hash = start_hash;
990 hinfo.minor_hash = 0;
f702ba0f 991 frame = dx_probe(NULL, dir, &hinfo, frames, &err);
ac27a0ec
DK		 992 if (!frame)
993 return err;
994
995 /* Add '.' and '..' from the htree header */
996 if (!start_hash && !start_minor_hash) {
617ba13b
MC		 997 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
998 if ((err = ext4_htree_store_dirent(dir_file, 0, 0, de)) != 0)
ac27a0ec
DK		 999 goto errout;
1000 count++;
1001 }
1002 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
617ba13b 1003 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
3d0518f4 1004 de = ext4_next_entry(de, dir->i_sb->s_blocksize);
617ba13b 1005 if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
ac27a0ec
DK		 1006 goto errout;
1007 count++;
1008 }
1009
1010 while (1) {
1011 block = dx_get_block(frame->at);
1012 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
1013 start_hash, start_minor_hash);
1014 if (ret < 0) {
1015 err = ret;
1016 goto errout;
1017 }
1018 count += ret;
1019 hashval = ~0;
617ba13b 1020 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
ac27a0ec
DK		 1021 frame, frames, &hashval);
1022 *next_hash = hashval;
1023 if (ret < 0) {
1024 err = ret;
1025 goto errout;
1026 }
1027 /*
1028 * Stop if: (a) there are no more entries, or
1029 * (b) we have inserted at least one entry and the
1030 * next hash value is not a continuation
1031 */
1032 if ((ret == 0) ||
1033 (count && ((hashval & 1) == 0)))
1034 break;
1035 }
1036 dx_release(frames);
4776004f
TT		 1037 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1038 "next hash: %x\n", count, *next_hash));
ac27a0ec
DK		 1039 return count;
1040errout:
1041 dx_release(frames);
1042 return (err);
1043}
1044
7335cd3b
TM		 1045static inline int search_dirblock(struct buffer_head *bh,
1046 struct inode *dir,
1047 const struct qstr *d_name,
1048 unsigned int offset,
1049 struct ext4_dir_entry_2 **res_dir)
1050{
1051 return search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,
1052 d_name, offset, res_dir);
1053}
1054
ac27a0ec
DK		 1055/*
1056 * Directory block splitting, compacting
1057 */
1058
ef2b02d3
ES		 1059/*
1060 * Create map of hash values, offsets, and sizes, stored at end of block.
1061 * Returns number of entries mapped.
1062 */
8bad4597
TT		 1063static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
1064 struct dx_hash_info *hinfo,
1065 struct dx_map_entry *map_tail)
ac27a0ec
DK		 1066{
1067 int count = 0;
1068 char *base = (char *) de;
1069 struct dx_hash_info h = *hinfo;
1070
8bad4597 1071 while ((char *) de < base + blocksize) {
ac27a0ec 1072 if (de->name_len && de->inode) {
617ba13b 1073 ext4fs_dirhash(de->name, de->name_len, &h);
ac27a0ec
DK		 1074 map_tail--;
1075 map_tail->hash = h.hash;
9aee2286 1076 map_tail->offs = ((char *) de - base)>>2;
ef2b02d3 1077 map_tail->size = le16_to_cpu(de->rec_len);
ac27a0ec
DK		 1078 count++;
1079 cond_resched();
1080 }
1081 /* XXX: do we need to check rec_len == 0 case? -Chris */
3d0518f4 1082 de = ext4_next_entry(de, blocksize);
ac27a0ec
DK		 1083 }
1084 return count;
1085}
1086
ef2b02d3 1087/* Sort map by hash value */
ac27a0ec
DK		 1088static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1089{
63f57933
AM		 1090 struct dx_map_entry *p, *q, *top = map + count - 1;
1091 int more;
1092 /* Combsort until bubble sort doesn't suck */
1093 while (count > 2) {
1094 count = count*10/13;
1095 if (count - 9 < 2) /* 9, 10 -> 11 */
1096 count = 11;
1097 for (p = top, q = p - count; q >= map; p--, q--)
1098 if (p->hash < q->hash)
1099 swap(*p, *q);
1100 }
1101 /* Garden variety bubble sort */
1102 do {
1103 more = 0;
1104 q = top;
1105 while (q-- > map) {
1106 if (q[1].hash >= q[0].hash)
ac27a0ec 1107 continue;
63f57933
AM		 1108 swap(*(q+1), *q);
1109 more = 1;
ac27a0ec
DK		 1110 }
1111 } while(more);
1112}
1113
725d26d3 1114static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
ac27a0ec
DK		 1115{
1116 struct dx_entry *entries = frame->entries;
1117 struct dx_entry *old = frame->at, *new = old + 1;
1118 int count = dx_get_count(entries);
1119
1120 assert(count < dx_get_limit(entries));
1121 assert(old < entries + count);
1122 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1123 dx_set_hash(new, hash);
1124 dx_set_block(new, block);
1125 dx_set_count(entries, count + 1);
1126}
ac27a0ec 1127
ac27a0ec 1128/*
617ba13b 1129 * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
ac27a0ec 1130 *
617ba13b 1131 * `len <= EXT4_NAME_LEN' is guaranteed by caller.
ac27a0ec
DK		 1132 * `de != NULL' is guaranteed by caller.
1133 */
617ba13b
MC		 1134static inline int ext4_match (int len, const char * const name,
1135 struct ext4_dir_entry_2 * de)
ac27a0ec
DK		 1136{
1137 if (len != de->name_len)
1138 return 0;
1139 if (!de->inode)
1140 return 0;
1141 return !memcmp(name, de->name, len);
1142}
1143
1144/*
1145 * Returns 0 if not found, -1 on failure, and 1 on success
1146 */
7335cd3b
TM		 1147int search_dir(struct buffer_head *bh,
1148 char *search_buf,
1149 int buf_size,
1150 struct inode *dir,
1151 const struct qstr *d_name,
1152 unsigned int offset,
1153 struct ext4_dir_entry_2 **res_dir)
ac27a0ec 1154{
617ba13b 1155 struct ext4_dir_entry_2 * de;
ac27a0ec
DK		 1156 char * dlimit;
1157 int de_len;
f702ba0f
TT		 1158 const char *name = d_name->name;
1159 int namelen = d_name->len;
ac27a0ec 1160
7335cd3b
TM		 1161 de = (struct ext4_dir_entry_2 *)search_buf;
1162 dlimit = search_buf + buf_size;
ac27a0ec
DK		 1163 while ((char *) de < dlimit) {
1164 /* this code is executed quadratically often */
1165 /* do minimal checking `by hand' */
1166
1167 if ((char *) de + namelen <= dlimit &&
617ba13b 1168 ext4_match (namelen, name, de)) {
ac27a0ec 1169 /* found a match - just to be sure, do a full check */
226ba972
TM		 1170 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
1171 bh->b_size, offset))
ac27a0ec
DK		 1172 return -1;
1173 *res_dir = de;
1174 return 1;
1175 }
1176 /* prevent looping on a bad block */
3d0518f4
WY		 1177 de_len = ext4_rec_len_from_disk(de->rec_len,
1178 dir->i_sb->s_blocksize);
ac27a0ec
DK		 1179 if (de_len <= 0)
1180 return -1;
1181 offset += de_len;
617ba13b 1182 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
ac27a0ec
DK		 1183 }
1184 return 0;
1185}
1186
c6af8803
DW		 1187static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1188 struct ext4_dir_entry *de)
1189{
1190 struct super_block *sb = dir->i_sb;
1191
1192 if (!is_dx(dir))
1193 return 0;
1194 if (block == 0)
1195 return 1;
1196 if (de->inode == 0 &&
1197 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
1198 sb->s_blocksize)
1199 return 1;
1200 return 0;
1201}
ac27a0ec
DK		 1202
1203/*
617ba13b 1204 * ext4_find_entry()
ac27a0ec
DK		 1205 *
1206 * finds an entry in the specified directory with the wanted name. It
1207 * returns the cache buffer in which the entry was found, and the entry
1208 * itself (as a parameter - res_dir). It does NOT read the inode of the
1209 * entry - you'll have to do that yourself if you want to.
1210 *
1211 * The returned buffer_head has ->b_count elevated. The caller is expected
1212 * to brelse() it when appropriate.
1213 */
f702ba0f
TT		 1214static struct buffer_head * ext4_find_entry (struct inode *dir,
1215 const struct qstr *d_name,
32f7f22c
TM		 1216 struct ext4_dir_entry_2 **res_dir,
1217 int *inlined)
ac27a0ec 1218{
af5bc92d
TT		 1219 struct super_block *sb;
1220 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1221 struct buffer_head *bh, *ret = NULL;
725d26d3 1222 ext4_lblk_t start, block, b;
8941ec8b 1223 const u8 *name = d_name->name;
ac27a0ec
DK		 1224 int ra_max = 0; /* Number of bh's in the readahead
1225 buffer, bh_use[] */
1226 int ra_ptr = 0; /* Current index into readahead
1227 buffer */
1228 int num = 0;
725d26d3
AK		 1229 ext4_lblk_t nblocks;
1230 int i, err;
ac27a0ec 1231 int namelen;
ac27a0ec
DK		 1232
1233 *res_dir = NULL;
1234 sb = dir->i_sb;
f702ba0f 1235 namelen = d_name->len;
617ba13b 1236 if (namelen > EXT4_NAME_LEN)
ac27a0ec 1237 return NULL;
e8e948e7
TM		 1238
1239 if (ext4_has_inline_data(dir)) {
1240 int has_inline_data = 1;
1241 ret = ext4_find_inline_entry(dir, d_name, res_dir,
1242 &has_inline_data);
32f7f22c
TM		 1243 if (has_inline_data) {
1244 if (inlined)
1245 *inlined = 1;
e8e948e7 1246 return ret;
32f7f22c 1247 }
e8e948e7
TM		 1248 }
1249
8941ec8b 1250 if ((namelen <= 2) && (name[0] == '.') &&
6d5c3aa8 1251 (name[1] == '.' || name[1] == '\0')) {
8941ec8b
TT		 1252 /*
1253 * "." or ".." will only be in the first block
1254 * NFS may look up ".."; "." should be handled by the VFS
1255 */
1256 block = start = 0;
1257 nblocks = 1;
1258 goto restart;
1259 }
ac27a0ec 1260 if (is_dx(dir)) {
f702ba0f 1261 bh = ext4_dx_find_entry(dir, d_name, res_dir, &err);
ac27a0ec
DK		 1262 /*
1263 * On success, or if the error was file not found,
1264 * return. Otherwise, fall back to doing a search the
1265 * old fashioned way.
1266 */
1267 if (bh || (err != ERR_BAD_DX_DIR))
1268 return bh;
4776004f
TT		 1269 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1270 "falling back\n"));
ac27a0ec 1271 }
617ba13b
MC		 1272 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1273 start = EXT4_I(dir)->i_dir_start_lookup;
ac27a0ec
DK		 1274 if (start >= nblocks)
1275 start = 0;
1276 block = start;
1277restart:
1278 do {
1279 /*
1280 * We deal with the read-ahead logic here.
1281 */
1282 if (ra_ptr >= ra_max) {
1283 /* Refill the readahead buffer */
1284 ra_ptr = 0;
1285 b = block;
1286 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
1287 /*
1288 * Terminate if we reach the end of the
1289 * directory and must wrap, or if our
1290 * search has finished at this block.
1291 */
1292 if (b >= nblocks || (num && block == start)) {
1293 bh_use[ra_max] = NULL;
1294 break;
1295 }
1296 num++;
617ba13b 1297 bh = ext4_getblk(NULL, dir, b++, 0, &err);
ac27a0ec
DK		 1298 bh_use[ra_max] = bh;
1299 if (bh)
65299a3b
CH		 1300 ll_rw_block(READ | REQ_META | REQ_PRIO,
1301 1, &bh);
ac27a0ec
DK		 1302 }
1303 }
1304 if ((bh = bh_use[ra_ptr++]) == NULL)
1305 goto next;
1306 wait_on_buffer(bh);
1307 if (!buffer_uptodate(bh)) {
1308 /* read error, skip block & hope for the best */
24676da4
TT		 1309 EXT4_ERROR_INODE(dir, "reading directory lblock %lu",
1310 (unsigned long) block);
ac27a0ec
DK		 1311 brelse(bh);
1312 goto next;
1313 }
b0336e8d 1314 if (!buffer_verified(bh) &&
c6af8803
DW		 1315 !is_dx_internal_node(dir, block,
1316 (struct ext4_dir_entry *)bh->b_data) &&
b0336e8d
DW		 1317 !ext4_dirent_csum_verify(dir,
1318 (struct ext4_dir_entry *)bh->b_data)) {
1319 EXT4_ERROR_INODE(dir, "checksumming directory "
1320 "block %lu", (unsigned long)block);
1321 brelse(bh);
1322 goto next;
1323 }
1324 set_buffer_verified(bh);
f702ba0f 1325 i = search_dirblock(bh, dir, d_name,
617ba13b 1326 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
ac27a0ec 1327 if (i == 1) {
617ba13b 1328 EXT4_I(dir)->i_dir_start_lookup = block;
ac27a0ec
DK		 1329 ret = bh;
1330 goto cleanup_and_exit;
1331 } else {
1332 brelse(bh);
1333 if (i < 0)
1334 goto cleanup_and_exit;
1335 }
1336 next:
1337 if (++block >= nblocks)
1338 block = 0;
1339 } while (block != start);
1340
1341 /*
1342 * If the directory has grown while we were searching, then
1343 * search the last part of the directory before giving up.
1344 */
1345 block = nblocks;
617ba13b 1346 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
ac27a0ec
DK		 1347 if (block < nblocks) {
1348 start = 0;
1349 goto restart;
1350 }
1351
1352cleanup_and_exit:
1353 /* Clean up the read-ahead blocks */
1354 for (; ra_ptr < ra_max; ra_ptr++)
af5bc92d 1355 brelse(bh_use[ra_ptr]);
ac27a0ec
DK		 1356 return ret;
1357}
1358
f702ba0f 1359static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct qstr *d_name,
617ba13b 1360 struct ext4_dir_entry_2 **res_dir, int *err)
ac27a0ec 1361{
8941ec8b 1362 struct super_block * sb = dir->i_sb;
ac27a0ec 1363 struct dx_hash_info hinfo;
ac27a0ec 1364 struct dx_frame frames[2], *frame;
ac27a0ec 1365 struct buffer_head *bh;
725d26d3 1366 ext4_lblk_t block;
ac27a0ec 1367 int retval;
ac27a0ec 1368
8941ec8b
TT		 1369 if (!(frame = dx_probe(d_name, dir, &hinfo, frames, err)))
1370 return NULL;
ac27a0ec
DK		 1371 do {
1372 block = dx_get_block(frame->at);
dc6982ff
TT		 1373 bh = ext4_read_dirblock(dir, block, DIRENT);
1374 if (IS_ERR(bh)) {
1375 *err = PTR_ERR(bh);
b0336e8d
DW		 1376 goto errout;
1377 }
7845c049
TT		 1378 retval = search_dirblock(bh, dir, d_name,
1379 block << EXT4_BLOCK_SIZE_BITS(sb),
1380 res_dir);
1381 if (retval == 1) { /* Success! */
1382 dx_release(frames);
1383 return bh;
ac27a0ec 1384 }
af5bc92d 1385 brelse(bh);
7845c049
TT		 1386 if (retval == -1) {
1387 *err = ERR_BAD_DX_DIR;
1388 goto errout;
1389 }
1390
ac27a0ec 1391 /* Check to see if we should continue to search */
8941ec8b 1392 retval = ext4_htree_next_block(dir, hinfo.hash, frame,
ac27a0ec
DK		 1393 frames, NULL);
1394 if (retval < 0) {
12062ddd 1395 ext4_warning(sb,
ac27a0ec
DK		 1396 "error reading index page in directory #%lu",
1397 dir->i_ino);
1398 *err = retval;
1399 goto errout;
1400 }
1401 } while (retval == 1);
1402
1403 *err = -ENOENT;
1404errout:
265c6a0f 1405 dxtrace(printk(KERN_DEBUG "%s not found\n", d_name->name));
ac27a0ec
DK		 1406 dx_release (frames);
1407 return NULL;
1408}
ac27a0ec 1409
00cd8dd3 1410static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
ac27a0ec 1411{
af5bc92d
TT		 1412 struct inode *inode;
1413 struct ext4_dir_entry_2 *de;
1414 struct buffer_head *bh;
ac27a0ec 1415
617ba13b 1416 if (dentry->d_name.len > EXT4_NAME_LEN)
ac27a0ec
DK		 1417 return ERR_PTR(-ENAMETOOLONG);
1418
32f7f22c 1419 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
ac27a0ec
DK		 1420 inode = NULL;
1421 if (bh) {
498e5f24 1422 __u32 ino = le32_to_cpu(de->inode);
af5bc92d 1423 brelse(bh);
617ba13b 1424 if (!ext4_valid_inum(dir->i_sb, ino)) {
24676da4 1425 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1d1fe1ee 1426 return ERR_PTR(-EIO);
a6c15c2b 1427 }
7e936b73 1428 if (unlikely(ino == dir->i_ino)) {
a34e15cc
DH		 1429 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",
1430 dentry);
7e936b73
AD		 1431 return ERR_PTR(-EIO);
1432 }
1d1fe1ee 1433 inode = ext4_iget(dir->i_sb, ino);
a9049376
AV		 1434 if (inode == ERR_PTR(-ESTALE)) {
1435 EXT4_ERROR_INODE(dir,
1436 "deleted inode referenced: %u",
1437 ino);
1438 return ERR_PTR(-EIO);
e6f009b0 1439 }
ac27a0ec
DK		 1440 }
1441 return d_splice_alias(inode, dentry);
1442}
1443
1444
617ba13b 1445struct dentry *ext4_get_parent(struct dentry *child)
ac27a0ec 1446{
498e5f24 1447 __u32 ino;
26fe5750 1448 static const struct qstr dotdot = QSTR_INIT("..", 2);
617ba13b 1449 struct ext4_dir_entry_2 * de;
ac27a0ec
DK		 1450 struct buffer_head *bh;
1451
32f7f22c 1452 bh = ext4_find_entry(child->d_inode, &dotdot, &de, NULL);
ac27a0ec
DK		 1453 if (!bh)
1454 return ERR_PTR(-ENOENT);
1455 ino = le32_to_cpu(de->inode);
1456 brelse(bh);
1457
617ba13b 1458 if (!ext4_valid_inum(child->d_inode->i_sb, ino)) {
24676da4
TT		 1459 EXT4_ERROR_INODE(child->d_inode,
1460 "bad parent inode number: %u", ino);
1d1fe1ee 1461 return ERR_PTR(-EIO);
a6c15c2b
VA		 1462 }
1463
44003728 1464 return d_obtain_alias(ext4_iget(child->d_inode->i_sb, ino));
ac27a0ec
DK		 1465}
1466
ef2b02d3
ES		 1467/*
1468 * Move count entries from end of map between two memory locations.
1469 * Returns pointer to last entry moved.
1470 */
617ba13b 1471static struct ext4_dir_entry_2 *
3d0518f4
WY		 1472dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1473 unsigned blocksize)
ac27a0ec
DK		 1474{
1475 unsigned rec_len = 0;
1476
1477 while (count--) {
60e6679e 1478 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
9aee2286 1479 (from + (map->offs<<2));
617ba13b 1480 rec_len = EXT4_DIR_REC_LEN(de->name_len);
ac27a0ec 1481 memcpy (to, de, rec_len);
617ba13b 1482 ((struct ext4_dir_entry_2 *) to)->rec_len =
3d0518f4 1483 ext4_rec_len_to_disk(rec_len, blocksize);
ac27a0ec
DK		 1484 de->inode = 0;
1485 map++;
1486 to += rec_len;
1487 }
617ba13b 1488 return (struct ext4_dir_entry_2 *) (to - rec_len);
ac27a0ec
DK		 1489}
1490
ef2b02d3
ES		 1491/*
1492 * Compact each dir entry in the range to the minimal rec_len.
1493 * Returns pointer to last entry in range.
1494 */
8bad4597 1495static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
ac27a0ec 1496{
617ba13b 1497 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
ac27a0ec
DK		 1498 unsigned rec_len = 0;
1499
1500 prev = to = de;
8bad4597 1501 while ((char*)de < base + blocksize) {
3d0518f4 1502 next = ext4_next_entry(de, blocksize);
ac27a0ec 1503 if (de->inode && de->name_len) {
617ba13b 1504 rec_len = EXT4_DIR_REC_LEN(de->name_len);
ac27a0ec
DK		 1505 if (de > to)
1506 memmove(to, de, rec_len);
3d0518f4 1507 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
ac27a0ec 1508 prev = to;
617ba13b 1509 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
ac27a0ec
DK		 1510 }
1511 de = next;
1512 }
1513 return prev;
1514}
1515
ef2b02d3
ES		 1516/*
1517 * Split a full leaf block to make room for a new dir entry.
1518 * Allocate a new block, and move entries so that they are approx. equally full.
1519 * Returns pointer to de in block into which the new entry will be inserted.
1520 */
617ba13b 1521static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
ac27a0ec
DK		 1522 struct buffer_head **bh,struct dx_frame *frame,
1523 struct dx_hash_info *hinfo, int *error)
1524{
1525 unsigned blocksize = dir->i_sb->s_blocksize;
1526 unsigned count, continued;
1527 struct buffer_head *bh2;
725d26d3 1528 ext4_lblk_t newblock;
ac27a0ec
DK		 1529 u32 hash2;
1530 struct dx_map_entry *map;
1531 char *data1 = (*bh)->b_data, *data2;
59e315b4 1532 unsigned split, move, size;
617ba13b 1533 struct ext4_dir_entry_2 *de = NULL, *de2;
b0336e8d
DW		 1534 struct ext4_dir_entry_tail *t;
1535 int csum_size = 0;
59e315b4 1536 int err = 0, i;
ac27a0ec 1537
b0336e8d
DW		 1538 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
1539 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1540 csum_size = sizeof(struct ext4_dir_entry_tail);
1541
0f70b406
TT		 1542 bh2 = ext4_append(handle, dir, &newblock);
1543 if (IS_ERR(bh2)) {
ac27a0ec
DK		 1544 brelse(*bh);
1545 *bh = NULL;
0f70b406
TT		 1546 *error = PTR_ERR(bh2);
1547 return NULL;
ac27a0ec
DK		 1548 }
1549
1550 BUFFER_TRACE(*bh, "get_write_access");
617ba13b 1551 err = ext4_journal_get_write_access(handle, *bh);
fedee54d
DM		 1552 if (err)
1553 goto journal_error;
1554
ac27a0ec 1555 BUFFER_TRACE(frame->bh, "get_write_access");
617ba13b 1556 err = ext4_journal_get_write_access(handle, frame->bh);
ac27a0ec
DK		 1557 if (err)
1558 goto journal_error;
1559
1560 data2 = bh2->b_data;
1561
1562 /* create map in the end of data2 block */
1563 map = (struct dx_map_entry *) (data2 + blocksize);
af5bc92d 1564 count = dx_make_map((struct ext4_dir_entry_2 *) data1,
ac27a0ec
DK		 1565 blocksize, hinfo, map);
1566 map -= count;
af5bc92d 1567 dx_sort_map(map, count);
ef2b02d3
ES		 1568 /* Split the existing block in the middle, size-wise */
1569 size = 0;
1570 move = 0;
1571 for (i = count-1; i >= 0; i--) {
1572 /* is more than half of this entry in 2nd half of the block? */
1573 if (size + map[i].size/2 > blocksize/2)
1574 break;
1575 size += map[i].size;
1576 move++;
1577 }
1578 /* map index at which we will split */
1579 split = count - move;
ac27a0ec
DK		 1580 hash2 = map[split].hash;
1581 continued = hash2 == map[split - 1].hash;
725d26d3
AK		 1582 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1583 (unsigned long)dx_get_block(frame->at),
1584 hash2, split, count-split));
ac27a0ec
DK		 1585
1586 /* Fancy dance to stay within two buffers */
3d0518f4 1587 de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize);
af5bc92d 1588 de = dx_pack_dirents(data1, blocksize);
b0336e8d
DW		 1589 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1590 (char *) de,
3d0518f4 1591 blocksize);
b0336e8d
DW		 1592 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1593 (char *) de2,
3d0518f4 1594 blocksize);
b0336e8d
DW		 1595 if (csum_size) {
1596 t = EXT4_DIRENT_TAIL(data2, blocksize);
1597 initialize_dirent_tail(t, blocksize);
1598
1599 t = EXT4_DIRENT_TAIL(data1, blocksize);
1600 initialize_dirent_tail(t, blocksize);
1601 }
1602
617ba13b
MC		 1603 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
1604 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
ac27a0ec
DK		 1605
1606 /* Which block gets the new entry? */
1607 if (hinfo->hash >= hash2)
1608 {
1609 swap(*bh, bh2);
1610 de = de2;
1611 }
af5bc92d 1612 dx_insert_block(frame, hash2 + continued, newblock);
b0336e8d 1613 err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
ac27a0ec
DK		 1614 if (err)
1615 goto journal_error;
dbe89444 1616 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
ac27a0ec
DK		 1617 if (err)
1618 goto journal_error;
af5bc92d
TT		 1619 brelse(bh2);
1620 dxtrace(dx_show_index("frame", frame->entries));
ac27a0ec 1621 return de;
fedee54d
DM		 1622
1623journal_error:
1624 brelse(*bh);
1625 brelse(bh2);
1626 *bh = NULL;
1627 ext4_std_error(dir->i_sb, err);
fedee54d
DM		 1628 *error = err;
1629 return NULL;
ac27a0ec 1630}
ac27a0ec 1631
978fef91
TM		 1632int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1633 struct buffer_head *bh,
1634 void *buf, int buf_size,
1635 const char *name, int namelen,
1636 struct ext4_dir_entry_2 **dest_de)
1637{
1638 struct ext4_dir_entry_2 *de;
1639 unsigned short reclen = EXT4_DIR_REC_LEN(namelen);
1640 int nlen, rlen;
1641 unsigned int offset = 0;
1642 char *top;
1643
1644 de = (struct ext4_dir_entry_2 *)buf;
1645 top = buf + buf_size - reclen;
1646 while ((char *) de <= top) {
1647 if (ext4_check_dir_entry(dir, NULL, de, bh,
1648 buf, buf_size, offset))
1649 return -EIO;
1650 if (ext4_match(namelen, name, de))
1651 return -EEXIST;
1652 nlen = EXT4_DIR_REC_LEN(de->name_len);
1653 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1654 if ((de->inode ? rlen - nlen : rlen) >= reclen)
1655 break;
1656 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1657 offset += rlen;
1658 }
1659 if ((char *) de > top)
1660 return -ENOSPC;
1661
1662 *dest_de = de;
1663 return 0;
1664}
1665
1666void ext4_insert_dentry(struct inode *inode,
1667 struct ext4_dir_entry_2 *de,
1668 int buf_size,
1669 const char *name, int namelen)
1670{
1671
1672 int nlen, rlen;
1673
1674 nlen = EXT4_DIR_REC_LEN(de->name_len);
1675 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1676 if (de->inode) {
1677 struct ext4_dir_entry_2 *de1 =
1678 (struct ext4_dir_entry_2 *)((char *)de + nlen);
1679 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
1680 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
1681 de = de1;
1682 }
1683 de->file_type = EXT4_FT_UNKNOWN;
1684 de->inode = cpu_to_le32(inode->i_ino);
1685 ext4_set_de_type(inode->i_sb, de, inode->i_mode);
1686 de->name_len = namelen;
1687 memcpy(de->name, name, namelen);
1688}
ac27a0ec
DK		 1689/*
1690 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1691 * it points to a directory entry which is guaranteed to be large
1692 * enough for new directory entry. If de is NULL, then
1693 * add_dirent_to_buf will attempt search the directory block for
1694 * space. It will return -ENOSPC if no space is available, and -EIO
1695 * and -EEXIST if directory entry already exists.
ac27a0ec
DK		 1696 */
1697static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
617ba13b 1698 struct inode *inode, struct ext4_dir_entry_2 *de,
af5bc92d 1699 struct buffer_head *bh)
ac27a0ec
DK		 1700{
1701 struct inode *dir = dentry->d_parent->d_inode;
1702 const char *name = dentry->d_name.name;
1703 int namelen = dentry->d_name.len;
3d0518f4 1704 unsigned int blocksize = dir->i_sb->s_blocksize;
b0336e8d 1705 int csum_size = 0;
978fef91 1706 int err;
b0336e8d
DW		 1707
1708 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1709 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1710 csum_size = sizeof(struct ext4_dir_entry_tail);
ac27a0ec 1711
ac27a0ec 1712 if (!de) {
978fef91
TM		 1713 err = ext4_find_dest_de(dir, inode,
1714 bh, bh->b_data, blocksize - csum_size,
1715 name, namelen, &de);
1716 if (err)
1717 return err;
ac27a0ec
DK		 1718 }
1719 BUFFER_TRACE(bh, "get_write_access");
617ba13b 1720 err = ext4_journal_get_write_access(handle, bh);
ac27a0ec 1721 if (err) {
617ba13b 1722 ext4_std_error(dir->i_sb, err);
ac27a0ec
DK		 1723 return err;
1724 }
1725
1726 /* By now the buffer is marked for journaling */
978fef91
TM		 1727 ext4_insert_dentry(inode, de, blocksize, name, namelen);
1728
ac27a0ec
DK		 1729 /*
1730 * XXX shouldn't update any times until successful
1731 * completion of syscall, but too many callers depend
1732 * on this.
1733 *
1734 * XXX similarly, too many callers depend on
617ba13b 1735 * ext4_new_inode() setting the times, but error
ac27a0ec
DK		 1736 * recovery deletes the inode, so the worst that can
1737 * happen is that the times are slightly out of date
1738 * and/or different from the directory change time.
1739 */
ef7f3835 1740 dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
617ba13b 1741 ext4_update_dx_flag(dir);
ac27a0ec 1742 dir->i_version++;
617ba13b 1743 ext4_mark_inode_dirty(handle, dir);
0390131b 1744 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
b0336e8d 1745 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
ac27a0ec 1746 if (err)
617ba13b 1747 ext4_std_error(dir->i_sb, err);
ac27a0ec
DK		 1748 return 0;
1749}
1750
ac27a0ec
DK		 1751/*
1752 * This converts a one block unindexed directory to a 3 block indexed
1753 * directory, and adds the dentry to the indexed directory.
1754 */
1755static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1756 struct inode *inode, struct buffer_head *bh)
1757{
1758 struct inode *dir = dentry->d_parent->d_inode;
1759 const char *name = dentry->d_name.name;
1760 int namelen = dentry->d_name.len;
1761 struct buffer_head *bh2;
1762 struct dx_root *root;
1763 struct dx_frame frames[2], *frame;
1764 struct dx_entry *entries;
617ba13b 1765 struct ext4_dir_entry_2 *de, *de2;
b0336e8d 1766 struct ext4_dir_entry_tail *t;
ac27a0ec
DK		 1767 char *data1, *top;
1768 unsigned len;
1769 int retval;
1770 unsigned blocksize;
1771 struct dx_hash_info hinfo;
725d26d3 1772 ext4_lblk_t block;
ac27a0ec 1773 struct fake_dirent *fde;
b0336e8d
DW		 1774 int csum_size = 0;
1775
1776 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1777 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1778 csum_size = sizeof(struct ext4_dir_entry_tail);
ac27a0ec
DK		 1779
1780 blocksize = dir->i_sb->s_blocksize;
e6b8bc09 1781 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
5d601255 1782 BUFFER_TRACE(bh, "get_write_access");
617ba13b 1783 retval = ext4_journal_get_write_access(handle, bh);
ac27a0ec 1784 if (retval) {
617ba13b 1785 ext4_std_error(dir->i_sb, retval);
ac27a0ec
DK		 1786 brelse(bh);
1787 return retval;
1788 }
1789 root = (struct dx_root *) bh->b_data;
1790
e6b8bc09
TT		 1791 /* The 0th block becomes the root, move the dirents out */
1792 fde = &root->dotdot;
1793 de = (struct ext4_dir_entry_2 *)((char *)fde +
3d0518f4 1794 ext4_rec_len_from_disk(fde->rec_len, blocksize));
e6b8bc09 1795 if ((char *) de >= (((char *) root) + blocksize)) {
24676da4 1796 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
e6b8bc09
TT		 1797 brelse(bh);
1798 return -EIO;
1799 }
b0336e8d 1800 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
e6b8bc09
TT		 1801
1802 /* Allocate new block for the 0th block's dirents */
0f70b406
TT		 1803 bh2 = ext4_append(handle, dir, &block);
1804 if (IS_ERR(bh2)) {
ac27a0ec 1805 brelse(bh);
0f70b406 1806 return PTR_ERR(bh2);
ac27a0ec 1807 }
12e9b892 1808 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
ac27a0ec
DK		 1809 data1 = bh2->b_data;
1810
ac27a0ec 1811 memcpy (data1, de, len);
617ba13b 1812 de = (struct ext4_dir_entry_2 *) data1;
ac27a0ec 1813 top = data1 + len;
3d0518f4 1814 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
ac27a0ec 1815 de = de2;
b0336e8d
DW		 1816 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1817 (char *) de,
3d0518f4 1818 blocksize);
b0336e8d
DW		 1819
1820 if (csum_size) {
1821 t = EXT4_DIRENT_TAIL(data1, blocksize);
1822 initialize_dirent_tail(t, blocksize);
1823 }
1824
ac27a0ec 1825 /* Initialize the root; the dot dirents already exist */
617ba13b 1826 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
3d0518f4
WY		 1827 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
1828 blocksize);
ac27a0ec
DK		 1829 memset (&root->info, 0, sizeof(root->info));
1830 root->info.info_length = sizeof(root->info);
617ba13b 1831 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
ac27a0ec 1832 entries = root->entries;
af5bc92d
TT		 1833 dx_set_block(entries, 1);
1834 dx_set_count(entries, 1);
1835 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
ac27a0ec
DK		 1836
1837 /* Initialize as for dx_probe */
1838 hinfo.hash_version = root->info.hash_version;
f99b2589
TT		 1839 if (hinfo.hash_version <= DX_HASH_TEA)
1840 hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
617ba13b
MC		 1841 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1842 ext4fs_dirhash(name, namelen, &hinfo);
ac27a0ec
DK		 1843 frame = frames;
1844 frame->entries = entries;
1845 frame->at = entries;
1846 frame->bh = bh;
1847 bh = bh2;
6976a6f2 1848
dbe89444 1849 ext4_handle_dirty_dx_node(handle, dir, frame->bh);
b0336e8d 1850 ext4_handle_dirty_dirent_node(handle, dir, bh);
6976a6f2 1851
ac27a0ec 1852 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
7ad8e4e6
JK		 1853 if (!de) {
1854 /*
1855 * Even if the block split failed, we have to properly write
1856 * out all the changes we did so far. Otherwise we can end up
1857 * with corrupted filesystem.
1858 */
1859 ext4_mark_inode_dirty(handle, dir);
7ad8e4e6 1860 dx_release(frames);
ac27a0ec 1861 return retval;
7ad8e4e6
JK		 1862 }
1863 dx_release(frames);
ac27a0ec 1864
2de770a4
TT		 1865 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1866 brelse(bh);
1867 return retval;
ac27a0ec 1868}
ac27a0ec
DK		 1869
1870/*
617ba13b 1871 * ext4_add_entry()
ac27a0ec
DK		 1872 *
1873 * adds a file entry to the specified directory, using the same
617ba13b 1874 * semantics as ext4_find_entry(). It returns NULL if it failed.
ac27a0ec
DK		 1875 *
1876 * NOTE!! The inode part of 'de' is left at 0 - which means you
1877 * may not sleep between calling this and putting something into
1878 * the entry, as someone else might have used it while you slept.
1879 */
af5bc92d
TT		 1880static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
1881 struct inode *inode)
ac27a0ec
DK		 1882{
1883 struct inode *dir = dentry->d_parent->d_inode;
af5bc92d 1884 struct buffer_head *bh;
617ba13b 1885 struct ext4_dir_entry_2 *de;
b0336e8d 1886 struct ext4_dir_entry_tail *t;
af5bc92d 1887 struct super_block *sb;
ac27a0ec 1888 int retval;
ac27a0ec 1889 int dx_fallback=0;
ac27a0ec 1890 unsigned blocksize;
725d26d3 1891 ext4_lblk_t block, blocks;
b0336e8d
DW		 1892 int csum_size = 0;
1893
1894 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1895 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1896 csum_size = sizeof(struct ext4_dir_entry_tail);
ac27a0ec
DK		 1897
1898 sb = dir->i_sb;
1899 blocksize = sb->s_blocksize;
1900 if (!dentry->d_name.len)
1901 return -EINVAL;
3c47d541
TM		 1902
1903 if (ext4_has_inline_data(dir)) {
1904 retval = ext4_try_add_inline_entry(handle, dentry, inode);
1905 if (retval < 0)
1906 return retval;
1907 if (retval == 1) {
1908 retval = 0;
1909 return retval;
1910 }
1911 }
1912
ac27a0ec 1913 if (is_dx(dir)) {
617ba13b 1914 retval = ext4_dx_add_entry(handle, dentry, inode);
ac27a0ec
DK		 1915 if (!retval || (retval != ERR_BAD_DX_DIR))
1916 return retval;
12e9b892 1917 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
ac27a0ec 1918 dx_fallback++;
617ba13b 1919 ext4_mark_inode_dirty(handle, dir);
ac27a0ec 1920 }
ac27a0ec 1921 blocks = dir->i_size >> sb->s_blocksize_bits;
498e5f24 1922 for (block = 0; block < blocks; block++) {
dc6982ff
TT		 1923 bh = ext4_read_dirblock(dir, block, DIRENT);
1924 if (IS_ERR(bh))
1925 return PTR_ERR(bh);
1926
ac27a0ec 1927 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
2de770a4
TT		 1928 if (retval != -ENOSPC) {
1929 brelse(bh);
ac27a0ec 1930 return retval;
2de770a4 1931 }
ac27a0ec 1932
ac27a0ec 1933 if (blocks == 1 && !dx_fallback &&
1e424a34
TT		 1934 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
1935 return make_indexed_dir(handle, dentry, inode, bh);
ac27a0ec
DK		 1936 brelse(bh);
1937 }
0f70b406
TT		 1938 bh = ext4_append(handle, dir, &block);
1939 if (IS_ERR(bh))
1940 return PTR_ERR(bh);
617ba13b 1941 de = (struct ext4_dir_entry_2 *) bh->b_data;
ac27a0ec 1942 de->inode = 0;
b0336e8d
DW		 1943 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
1944
1945 if (csum_size) {
1946 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
1947 initialize_dirent_tail(t, blocksize);
1948 }
1949
2de770a4
TT		 1950 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1951 brelse(bh);
14ece102
FM		 1952 if (retval == 0)
1953 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
2de770a4 1954 return retval;
ac27a0ec
DK		 1955}
1956
ac27a0ec
DK		 1957/*
1958 * Returns 0 for success, or a negative error value
1959 */
617ba13b 1960static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
ac27a0ec
DK		 1961 struct inode *inode)
1962{
1963 struct dx_frame frames[2], *frame;
1964 struct dx_entry *entries, *at;
1965 struct dx_hash_info hinfo;
af5bc92d 1966 struct buffer_head *bh;
ac27a0ec 1967 struct inode *dir = dentry->d_parent->d_inode;
af5bc92d 1968 struct super_block *sb = dir->i_sb;
617ba13b 1969 struct ext4_dir_entry_2 *de;
ac27a0ec
DK		 1970 int err;
1971
f702ba0f 1972 frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err);
ac27a0ec
DK		 1973 if (!frame)
1974 return err;
1975 entries = frame->entries;
1976 at = frame->at;
dc6982ff
TT		 1977 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT);
1978 if (IS_ERR(bh)) {
1979 err = PTR_ERR(bh);
1980 bh = NULL;
ac27a0ec 1981 goto cleanup;
6d1ab10e 1982 }
ac27a0ec
DK		 1983
1984 BUFFER_TRACE(bh, "get_write_access");
617ba13b 1985 err = ext4_journal_get_write_access(handle, bh);
ac27a0ec
DK		 1986 if (err)
1987 goto journal_error;
1988
1989 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
2de770a4 1990 if (err != -ENOSPC)
ac27a0ec 1991 goto cleanup;
ac27a0ec
DK		 1992
1993 /* Block full, should compress but for now just split */
4776004f 1994 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
ac27a0ec
DK		 1995 dx_get_count(entries), dx_get_limit(entries)));
1996 /* Need to split index? */
1997 if (dx_get_count(entries) == dx_get_limit(entries)) {
725d26d3 1998 ext4_lblk_t newblock;
ac27a0ec
DK		 1999 unsigned icount = dx_get_count(entries);
2000 int levels = frame - frames;
2001 struct dx_entry *entries2;
2002 struct dx_node *node2;
2003 struct buffer_head *bh2;
2004
2005 if (levels && (dx_get_count(frames->entries) ==
2006 dx_get_limit(frames->entries))) {
12062ddd 2007 ext4_warning(sb, "Directory index full!");
ac27a0ec
DK		 2008 err = -ENOSPC;
2009 goto cleanup;
2010 }
0f70b406
TT		 2011 bh2 = ext4_append(handle, dir, &newblock);
2012 if (IS_ERR(bh2)) {
2013 err = PTR_ERR(bh2);
ac27a0ec 2014 goto cleanup;
0f70b406 2015 }
ac27a0ec
DK		 2016 node2 = (struct dx_node *)(bh2->b_data);
2017 entries2 = node2->entries;
1f7bebb9 2018 memset(&node2->fake, 0, sizeof(struct fake_dirent));
3d0518f4
WY		 2019 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
2020 sb->s_blocksize);
ac27a0ec 2021 BUFFER_TRACE(frame->bh, "get_write_access");
617ba13b 2022 err = ext4_journal_get_write_access(handle, frame->bh);
ac27a0ec
DK		 2023 if (err)
2024 goto journal_error;
2025 if (levels) {
2026 unsigned icount1 = icount/2, icount2 = icount - icount1;
2027 unsigned hash2 = dx_get_hash(entries + icount1);
4776004f
TT		 2028 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2029 icount1, icount2));
ac27a0ec
DK		 2030
2031 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
617ba13b 2032 err = ext4_journal_get_write_access(handle,
ac27a0ec
DK		 2033 frames[0].bh);
2034 if (err)
2035 goto journal_error;
2036
af5bc92d
TT		 2037 memcpy((char *) entries2, (char *) (entries + icount1),
2038 icount2 * sizeof(struct dx_entry));
2039 dx_set_count(entries, icount1);
2040 dx_set_count(entries2, icount2);
2041 dx_set_limit(entries2, dx_node_limit(dir));
ac27a0ec
DK		 2042
2043 /* Which index block gets the new entry? */
2044 if (at - entries >= icount1) {
2045 frame->at = at = at - entries - icount1 + entries2;
2046 frame->entries = entries = entries2;
2047 swap(frame->bh, bh2);
2048 }
af5bc92d
TT		 2049 dx_insert_block(frames + 0, hash2, newblock);
2050 dxtrace(dx_show_index("node", frames[1].entries));
2051 dxtrace(dx_show_index("node",
ac27a0ec 2052 ((struct dx_node *) bh2->b_data)->entries));
dbe89444 2053 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
ac27a0ec
DK		 2054 if (err)
2055 goto journal_error;
2056 brelse (bh2);
2057 } else {
4776004f
TT		 2058 dxtrace(printk(KERN_DEBUG
2059 "Creating second level index...\n"));
ac27a0ec
DK		 2060 memcpy((char *) entries2, (char *) entries,
2061 icount * sizeof(struct dx_entry));
2062 dx_set_limit(entries2, dx_node_limit(dir));
2063
2064 /* Set up root */
2065 dx_set_count(entries, 1);
2066 dx_set_block(entries + 0, newblock);
2067 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
2068
2069 /* Add new access path frame */
2070 frame = frames + 1;
2071 frame->at = at = at - entries + entries2;
2072 frame->entries = entries = entries2;
2073 frame->bh = bh2;
617ba13b 2074 err = ext4_journal_get_write_access(handle,
ac27a0ec
DK		 2075 frame->bh);
2076 if (err)
2077 goto journal_error;
2078 }
dbe89444 2079 err = ext4_handle_dirty_dx_node(handle, dir, frames[0].bh);
b4097142
TT		 2080 if (err) {
2081 ext4_std_error(inode->i_sb, err);
2082 goto cleanup;
2083 }
ac27a0ec
DK		 2084 }
2085 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
2086 if (!de)
2087 goto cleanup;
2088 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
ac27a0ec
DK		 2089 goto cleanup;
2090
2091journal_error:
617ba13b 2092 ext4_std_error(dir->i_sb, err);
ac27a0ec 2093cleanup:
b1deefc9 2094 brelse(bh);
ac27a0ec
DK		 2095 dx_release(frames);
2096 return err;
2097}
ac27a0ec
DK		 2098
2099/*
05019a9e
TM		 2100 * ext4_generic_delete_entry deletes a directory entry by merging it
2101 * with the previous entry
ac27a0ec 2102 */
05019a9e
TM		 2103int ext4_generic_delete_entry(handle_t *handle,
2104 struct inode *dir,
2105 struct ext4_dir_entry_2 *de_del,
2106 struct buffer_head *bh,
2107 void *entry_buf,
2108 int buf_size,
2109 int csum_size)
ac27a0ec 2110{
af5bc92d 2111 struct ext4_dir_entry_2 *de, *pde;
3d0518f4 2112 unsigned int blocksize = dir->i_sb->s_blocksize;
05019a9e 2113 int i;
b0336e8d 2114
ac27a0ec
DK		 2115 i = 0;
2116 pde = NULL;
05019a9e
TM		 2117 de = (struct ext4_dir_entry_2 *)entry_buf;
2118 while (i < buf_size - csum_size) {
226ba972
TM		 2119 if (ext4_check_dir_entry(dir, NULL, de, bh,
2120 bh->b_data, bh->b_size, i))
ac27a0ec
DK		 2121 return -EIO;
2122 if (de == de_del) {
ac27a0ec 2123 if (pde)
a72d7f83 2124 pde->rec_len = ext4_rec_len_to_disk(
3d0518f4
WY		 2125 ext4_rec_len_from_disk(pde->rec_len,
2126 blocksize) +
2127 ext4_rec_len_from_disk(de->rec_len,
2128 blocksize),
2129 blocksize);
ac27a0ec
DK		 2130 else
2131 de->inode = 0;
2132 dir->i_version++;
ac27a0ec
DK		 2133 return 0;
2134 }
3d0518f4 2135 i += ext4_rec_len_from_disk(de->rec_len, blocksize);
ac27a0ec 2136 pde = de;
3d0518f4 2137 de = ext4_next_entry(de, blocksize);
ac27a0ec
DK		 2138 }
2139 return -ENOENT;
2140}
2141
05019a9e
TM		 2142static int ext4_delete_entry(handle_t *handle,
2143 struct inode *dir,
2144 struct ext4_dir_entry_2 *de_del,
2145 struct buffer_head *bh)
2146{
2147 int err, csum_size = 0;
2148
9f40fe54
TM		 2149 if (ext4_has_inline_data(dir)) {
2150 int has_inline_data = 1;
2151 err = ext4_delete_inline_entry(handle, dir, de_del, bh,
2152 &has_inline_data);
2153 if (has_inline_data)
2154 return err;
2155 }
2156
05019a9e
TM		 2157 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2158 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2159 csum_size = sizeof(struct ext4_dir_entry_tail);
2160
2161 BUFFER_TRACE(bh, "get_write_access");
2162 err = ext4_journal_get_write_access(handle, bh);
2163 if (unlikely(err))
2164 goto out;
2165
2166 err = ext4_generic_delete_entry(handle, dir, de_del,
2167 bh, bh->b_data,
2168 dir->i_sb->s_blocksize, csum_size);
2169 if (err)
2170 goto out;
2171
2172 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
2173 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
2174 if (unlikely(err))
2175 goto out;
2176
2177 return 0;
2178out:
2179 if (err != -ENOENT)
2180 ext4_std_error(dir->i_sb, err);
2181 return err;
2182}
2183
f8628a14
AD		 2184/*
2185 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2,
2186 * since this indicates that nlinks count was previously 1.
2187 */
2188static void ext4_inc_count(handle_t *handle, struct inode *inode)
2189{
2190 inc_nlink(inode);
2191 if (is_dx(inode) && inode->i_nlink > 1) {
2192 /* limit is 16-bit i_links_count */
2193 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) {
bfe86848 2194 set_nlink(inode, 1);
f8628a14
AD		 2195 EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb,
2196 EXT4_FEATURE_RO_COMPAT_DIR_NLINK);
2197 }
2198 }
2199}
2200
2201/*
2202 * If a directory had nlink == 1, then we should let it be 1. This indicates
2203 * directory has >EXT4_LINK_MAX subdirs.
2204 */
2205static void ext4_dec_count(handle_t *handle, struct inode *inode)
2206{
909a4cf1
AD		 2207 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2208 drop_nlink(inode);
f8628a14
AD		 2209}
2210
2211
617ba13b 2212static int ext4_add_nondir(handle_t *handle,
ac27a0ec
DK		 2213 struct dentry *dentry, struct inode *inode)
2214{
617ba13b 2215 int err = ext4_add_entry(handle, dentry, inode);
ac27a0ec 2216 if (!err) {
617ba13b 2217 ext4_mark_inode_dirty(handle, inode);
6b38e842 2218 unlock_new_inode(inode);
8fc37ec5 2219 d_instantiate(dentry, inode);
ac27a0ec
DK		 2220 return 0;
2221 }
731b9a54 2222 drop_nlink(inode);
6b38e842 2223 unlock_new_inode(inode);
ac27a0ec
DK		 2224 iput(inode);
2225 return err;
2226}
2227
2228/*
2229 * By the time this is called, we already have created
2230 * the directory cache entry for the new file, but it
2231 * is so far negative - it has no inode.
2232 *
2233 * If the create succeeds, we fill in the inode information
2234 * with d_instantiate().
2235 */
4acdaf27 2236static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
ebfc3b49 2237 bool excl)
ac27a0ec
DK		 2238{
2239 handle_t *handle;
af5bc92d 2240 struct inode *inode;
1139575a 2241 int err, credits, retries = 0;
ac27a0ec 2242
871a2931 2243 dquot_initialize(dir);
907f4554 2244
1139575a 2245 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
eb9cc7e1 2246 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
ac27a0ec 2247retry:
1139575a
TT		 2248 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2249 NULL, EXT4_HT_DIR, credits);
2250 handle = ext4_journal_current_handle();
ac27a0ec
DK		 2251 err = PTR_ERR(inode);
2252 if (!IS_ERR(inode)) {
617ba13b
MC		 2253 inode->i_op = &ext4_file_inode_operations;
2254 inode->i_fop = &ext4_file_operations;
2255 ext4_set_aops(inode);
2256 err = ext4_add_nondir(handle, dentry, inode);
1139575a
TT		 2257 if (!err && IS_DIRSYNC(dir))
2258 ext4_handle_sync(handle);
ac27a0ec 2259 }
1139575a
TT		 2260 if (handle)
2261 ext4_journal_stop(handle);
617ba13b 2262 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2263 goto retry;
2264 return err;
2265}
2266
af5bc92d 2267static int ext4_mknod(struct inode *dir, struct dentry *dentry,
1a67aafb 2268 umode_t mode, dev_t rdev)
ac27a0ec
DK		 2269{
2270 handle_t *handle;
2271 struct inode *inode;
1139575a 2272 int err, credits, retries = 0;
ac27a0ec
DK		 2273
2274 if (!new_valid_dev(rdev))
2275 return -EINVAL;
2276
871a2931 2277 dquot_initialize(dir);
907f4554 2278
1139575a 2279 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
eb9cc7e1 2280 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
ac27a0ec 2281retry:
1139575a
TT		 2282 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
2283 NULL, EXT4_HT_DIR, credits);
2284 handle = ext4_journal_current_handle();
ac27a0ec
DK		 2285 err = PTR_ERR(inode);
2286 if (!IS_ERR(inode)) {
2287 init_special_inode(inode, inode->i_mode, rdev);
617ba13b 2288 inode->i_op = &ext4_special_inode_operations;
617ba13b 2289 err = ext4_add_nondir(handle, dentry, inode);
1139575a
TT		 2290 if (!err && IS_DIRSYNC(dir))
2291 ext4_handle_sync(handle);
ac27a0ec 2292 }
1139575a
TT		 2293 if (handle)
2294 ext4_journal_stop(handle);
617ba13b 2295 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2296 goto retry;
2297 return err;
2298}
2299
af51a2ac
AV		 2300static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
2301{
2302 handle_t *handle;
2303 struct inode *inode;
2304 int err, retries = 0;
2305
2306 dquot_initialize(dir);
2307
2308retry:
2309 inode = ext4_new_inode_start_handle(dir, mode,
2310 NULL, 0, NULL,
2311 EXT4_HT_DIR,
2312 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2313 4 + EXT4_XATTR_TRANS_BLOCKS);
2314 handle = ext4_journal_current_handle();
2315 err = PTR_ERR(inode);
2316 if (!IS_ERR(inode)) {
2317 inode->i_op = &ext4_file_inode_operations;
2318 inode->i_fop = &ext4_file_operations;
2319 ext4_set_aops(inode);
e94bd349 2320 d_tmpfile(dentry, inode);
af51a2ac
AV		 2321 err = ext4_orphan_add(handle, inode);
2322 if (err)
43ae9e3f 2323 goto err_unlock_inode;
af51a2ac 2324 mark_inode_dirty(inode);
af51a2ac
AV		 2325 unlock_new_inode(inode);
2326 }
2327 if (handle)
2328 ext4_journal_stop(handle);
2329 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
2330 goto retry;
2331 return err;
43ae9e3f 2332err_unlock_inode:
af51a2ac
AV		 2333 ext4_journal_stop(handle);
2334 unlock_new_inode(inode);
af51a2ac
AV		 2335 return err;
2336}
2337
a774f9c2
TM		 2338struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2339 struct ext4_dir_entry_2 *de,
2340 int blocksize, int csum_size,
2341 unsigned int parent_ino, int dotdot_real_len)
2342{
2343 de->inode = cpu_to_le32(inode->i_ino);
2344 de->name_len = 1;
2345 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2346 blocksize);
2347 strcpy(de->name, ".");
2348 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2349
2350 de = ext4_next_entry(de, blocksize);
2351 de->inode = cpu_to_le32(parent_ino);
2352 de->name_len = 2;
2353 if (!dotdot_real_len)
2354 de->rec_len = ext4_rec_len_to_disk(blocksize -
2355 (csum_size + EXT4_DIR_REC_LEN(1)),
2356 blocksize);
2357 else
2358 de->rec_len = ext4_rec_len_to_disk(
2359 EXT4_DIR_REC_LEN(de->name_len), blocksize);
2360 strcpy(de->name, "..");
2361 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2362
2363 return ext4_next_entry(de, blocksize);
2364}
2365
2366static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2367 struct inode *inode)
ac27a0ec 2368{
dabd991f 2369 struct buffer_head *dir_block = NULL;
af5bc92d 2370 struct ext4_dir_entry_2 *de;
b0336e8d 2371 struct ext4_dir_entry_tail *t;
dc6982ff 2372 ext4_lblk_t block = 0;
3d0518f4 2373 unsigned int blocksize = dir->i_sb->s_blocksize;
b0336e8d 2374 int csum_size = 0;
a774f9c2 2375 int err;
ac27a0ec 2376
b0336e8d
DW		 2377 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2378 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2379 csum_size = sizeof(struct ext4_dir_entry_tail);
2380
3c47d541
TM		 2381 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
2382 err = ext4_try_create_inline_dir(handle, dir, inode);
2383 if (err < 0 && err != -ENOSPC)
2384 goto out;
2385 if (!err)
2386 goto out;
2387 }
2388
dc6982ff 2389 inode->i_size = 0;
0f70b406
TT		 2390 dir_block = ext4_append(handle, inode, &block);
2391 if (IS_ERR(dir_block))
2392 return PTR_ERR(dir_block);
a774f9c2
TM		 2393 BUFFER_TRACE(dir_block, "get_write_access");
2394 err = ext4_journal_get_write_access(handle, dir_block);
2395 if (err)
2396 goto out;
2397 de = (struct ext4_dir_entry_2 *)dir_block->b_data;
2398 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
2399 set_nlink(inode, 2);
2400 if (csum_size) {
2401 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
2402 initialize_dirent_tail(t, blocksize);
2403 }
2404
2405 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2406 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
2407 if (err)
2408 goto out;
2409 set_buffer_verified(dir_block);
2410out:
2411 brelse(dir_block);
2412 return err;
2413}
2414
2415static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2416{
2417 handle_t *handle;
2418 struct inode *inode;
1139575a 2419 int err, credits, retries = 0;
a774f9c2 2420
f8628a14 2421 if (EXT4_DIR_LINK_MAX(dir))
ac27a0ec
DK		 2422 return -EMLINK;
2423
871a2931 2424 dquot_initialize(dir);
907f4554 2425
1139575a 2426 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
eb9cc7e1 2427 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
ac27a0ec 2428retry:
1139575a
TT		 2429 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
2430 &dentry->d_name,
2431 0, NULL, EXT4_HT_DIR, credits);
2432 handle = ext4_journal_current_handle();
ac27a0ec
DK		 2433 err = PTR_ERR(inode);
2434 if (IS_ERR(inode))
2435 goto out_stop;
2436
617ba13b
MC		 2437 inode->i_op = &ext4_dir_inode_operations;
2438 inode->i_fop = &ext4_dir_operations;
a774f9c2 2439 err = ext4_init_new_dir(handle, dir, inode);
dabd991f
NK		 2440 if (err)
2441 goto out_clear_inode;
2442 err = ext4_mark_inode_dirty(handle, inode);
2443 if (!err)
2444 err = ext4_add_entry(handle, dentry, inode);
ac27a0ec 2445 if (err) {
4cdeed86
AK		 2446out_clear_inode:
2447 clear_nlink(inode);
6b38e842 2448 unlock_new_inode(inode);
617ba13b 2449 ext4_mark_inode_dirty(handle, inode);
af5bc92d 2450 iput(inode);
ac27a0ec
DK		 2451 goto out_stop;
2452 }
f8628a14 2453 ext4_inc_count(handle, dir);
617ba13b 2454 ext4_update_dx_flag(dir);
dabd991f
NK		 2455 err = ext4_mark_inode_dirty(handle, dir);
2456 if (err)
2457 goto out_clear_inode;
6b38e842 2458 unlock_new_inode(inode);
8fc37ec5 2459 d_instantiate(dentry, inode);
1139575a
TT		 2460 if (IS_DIRSYNC(dir))
2461 ext4_handle_sync(handle);
2462
ac27a0ec 2463out_stop:
1139575a
TT		 2464 if (handle)
2465 ext4_journal_stop(handle);
617ba13b 2466 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2467 goto retry;
2468 return err;
2469}
2470
2471/*
2472 * routine to check that the specified directory is empty (for rmdir)
2473 */
af5bc92d 2474static int empty_dir(struct inode *inode)
ac27a0ec 2475{
498e5f24 2476 unsigned int offset;
af5bc92d
TT		 2477 struct buffer_head *bh;
2478 struct ext4_dir_entry_2 *de, *de1;
2479 struct super_block *sb;
ac27a0ec
DK		 2480 int err = 0;
2481
61f86638
TM		 2482 if (ext4_has_inline_data(inode)) {
2483 int has_inline_data = 1;
2484
2485 err = empty_inline_dir(inode, &has_inline_data);
2486 if (has_inline_data)
2487 return err;
2488 }
2489
ac27a0ec 2490 sb = inode->i_sb;
dc6982ff
TT		 2491 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
2492 EXT4_ERROR_INODE(inode, "invalid size");
ac27a0ec
DK		 2493 return 1;
2494 }
dc6982ff
TT		 2495 bh = ext4_read_dirblock(inode, 0, EITHER);
2496 if (IS_ERR(bh))
2497 return 1;
2498
617ba13b 2499 de = (struct ext4_dir_entry_2 *) bh->b_data;
3d0518f4 2500 de1 = ext4_next_entry(de, sb->s_blocksize);
ac27a0ec
DK		 2501 if (le32_to_cpu(de->inode) != inode->i_ino ||
2502 !le32_to_cpu(de1->inode) ||
af5bc92d
TT		 2503 strcmp(".", de->name) ||
2504 strcmp("..", de1->name)) {
12062ddd 2505 ext4_warning(inode->i_sb,
af5bc92d
TT		 2506 "bad directory (dir #%lu) - no `.' or `..'",
2507 inode->i_ino);
2508 brelse(bh);
ac27a0ec
DK		 2509 return 1;
2510 }
3d0518f4
WY		 2511 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
2512 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
2513 de = ext4_next_entry(de1, sb->s_blocksize);
af5bc92d 2514 while (offset < inode->i_size) {
236f5ecb 2515 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
24676da4 2516 unsigned int lblock;
ac27a0ec 2517 err = 0;
af5bc92d 2518 brelse(bh);
24676da4 2519 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
dc6982ff
TT		 2520 bh = ext4_read_dirblock(inode, lblock, EITHER);
2521 if (IS_ERR(bh))
2522 return 1;
617ba13b 2523 de = (struct ext4_dir_entry_2 *) bh->b_data;
ac27a0ec 2524 }
226ba972
TM		 2525 if (ext4_check_dir_entry(inode, NULL, de, bh,
2526 bh->b_data, bh->b_size, offset)) {
617ba13b 2527 de = (struct ext4_dir_entry_2 *)(bh->b_data +
ac27a0ec
DK		 2528 sb->s_blocksize);
2529 offset = (offset | (sb->s_blocksize - 1)) + 1;
2530 continue;
2531 }
2532 if (le32_to_cpu(de->inode)) {
af5bc92d 2533 brelse(bh);
ac27a0ec
DK		 2534 return 0;
2535 }
3d0518f4
WY		 2536 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2537 de = ext4_next_entry(de, sb->s_blocksize);
ac27a0ec 2538 }
af5bc92d 2539 brelse(bh);
ac27a0ec
DK		 2540 return 1;
2541}
2542
d745a8c2
JK		 2543/*
2544 * ext4_orphan_add() links an unlinked or truncated inode into a list of
ac27a0ec
DK		 2545 * such inodes, starting at the superblock, in case we crash before the
2546 * file is closed/deleted, or in case the inode truncate spans multiple
2547 * transactions and the last transaction is not recovered after a crash.
2548 *
2549 * At filesystem recovery time, we walk this list deleting unlinked
617ba13b 2550 * inodes and truncating linked inodes in ext4_orphan_cleanup().
d745a8c2
JK		 2551 *
2552 * Orphan list manipulation functions must be called under i_mutex unless
2553 * we are just creating the inode or deleting it.
ac27a0ec 2554 */
617ba13b 2555int ext4_orphan_add(handle_t *handle, struct inode *inode)
ac27a0ec
DK		 2556{
2557 struct super_block *sb = inode->i_sb;
cd2c080c 2558 struct ext4_sb_info *sbi = EXT4_SB(sb);
617ba13b 2559 struct ext4_iloc iloc;
ac27a0ec 2560 int err = 0, rc;
d745a8c2 2561 bool dirty = false;
ac27a0ec 2562
cd2c080c 2563 if (!sbi->s_journal)
0390131b
FM		 2564 return 0;
2565
d745a8c2
JK		 2566 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
2567 !mutex_is_locked(&inode->i_mutex));
2568 /*
2569 * Exit early if inode already is on orphan list. This is a big speedup
2570 * since we don't have to contend on the global s_orphan_lock.
2571 */
617ba13b 2572 if (!list_empty(&EXT4_I(inode)->i_orphan))
d745a8c2 2573 return 0;
ac27a0ec 2574
afb86178
LC		 2575 /*
2576 * Orphan handling is only valid for files with data blocks
2577 * being truncated, or files being unlinked. Note that we either
2578 * hold i_mutex, or the inode can not be referenced from outside,
2579 * so i_nlink should not be bumped due to race
ac27a0ec 2580 */
af5bc92d
TT		 2581 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2582 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
ac27a0ec 2583
cd2c080c
JK		 2584 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2585 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
ac27a0ec 2586 if (err)
d745a8c2 2587 goto out;
ac27a0ec 2588
617ba13b 2589 err = ext4_reserve_inode_write(handle, inode, &iloc);
ac27a0ec 2590 if (err)
d745a8c2
JK		 2591 goto out;
2592
2593 mutex_lock(&sbi->s_orphan_lock);
6e3617e5
DM		 2594 /*
2595 * Due to previous errors inode may be already a part of on-disk
2596 * orphan list. If so skip on-disk list modification.
2597 */
d745a8c2
JK		 2598 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
2599 (le32_to_cpu(sbi->s_es->s_inodes_count))) {
2600 /* Insert this inode at the head of the on-disk orphan list */
2601 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
2602 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
2603 dirty = true;
2604 }
2605 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
2606 mutex_unlock(&sbi->s_orphan_lock);
ac27a0ec 2607
d745a8c2
JK		 2608 if (dirty) {
2609 err = ext4_handle_dirty_super(handle, sb);
2610 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
2611 if (!err)
2612 err = rc;
2613 if (err) {
2614 /*
2615 * We have to remove inode from in-memory list if
2616 * addition to on disk orphan list failed. Stray orphan
2617 * list entries can cause panics at unmount time.
2618 */
2619 mutex_lock(&sbi->s_orphan_lock);
2620 list_del(&EXT4_I(inode)->i_orphan);
2621 mutex_unlock(&sbi->s_orphan_lock);
2622 }
2623 }
ac27a0ec
DK		 2624 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
2625 jbd_debug(4, "orphan inode %lu will point to %d\n",
2626 inode->i_ino, NEXT_ORPHAN(inode));
d745a8c2 2627out:
cd2c080c 2628 ext4_std_error(sb, err);
ac27a0ec
DK		 2629 return err;
2630}
2631
2632/*
617ba13b 2633 * ext4_orphan_del() removes an unlinked or truncated inode from the list
ac27a0ec
DK		 2634 * of such inodes stored on disk, because it is finally being cleaned up.
2635 */
617ba13b 2636int ext4_orphan_del(handle_t *handle, struct inode *inode)
ac27a0ec
DK		 2637{
2638 struct list_head *prev;
617ba13b 2639 struct ext4_inode_info *ei = EXT4_I(inode);
cd2c080c 2640 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
498e5f24 2641 __u32 ino_next;
617ba13b 2642 struct ext4_iloc iloc;
ac27a0ec
DK		 2643 int err = 0;
2644
cd2c080c 2645 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
0390131b
FM		 2646 return 0;
2647
d745a8c2
JK		 2648 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
2649 !mutex_is_locked(&inode->i_mutex));
2650 /* Do this quick check before taking global s_orphan_lock. */
3b9d4ed2 2651 if (list_empty(&ei->i_orphan))
d745a8c2 2652 return 0;
ac27a0ec 2653
d745a8c2
JK		 2654 if (handle) {
2655 /* Grab inode buffer early before taking global s_orphan_lock */
2656 err = ext4_reserve_inode_write(handle, inode, &iloc);
2657 }
ac27a0ec 2658
d745a8c2 2659 mutex_lock(&sbi->s_orphan_lock);
ac27a0ec
DK		 2660 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
2661
d745a8c2 2662 prev = ei->i_orphan.prev;
ac27a0ec
DK		 2663 list_del_init(&ei->i_orphan);
2664
2665 /* If we're on an error path, we may not have a valid
2666 * transaction handle with which to update the orphan list on
2667 * disk, but we still need to remove the inode from the linked
2668 * list in memory. */
d745a8c2
JK		 2669 if (!handle || err) {
2670 mutex_unlock(&sbi->s_orphan_lock);
ac27a0ec 2671 goto out_err;
d745a8c2 2672 }
ac27a0ec 2673
d745a8c2 2674 ino_next = NEXT_ORPHAN(inode);
ac27a0ec 2675 if (prev == &sbi->s_orphan) {
498e5f24 2676 jbd_debug(4, "superblock will point to %u\n", ino_next);
ac27a0ec 2677 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
617ba13b 2678 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
d745a8c2
JK		 2679 if (err) {
2680 mutex_unlock(&sbi->s_orphan_lock);
ac27a0ec 2681 goto out_brelse;
d745a8c2 2682 }
ac27a0ec 2683 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
d745a8c2 2684 mutex_unlock(&sbi->s_orphan_lock);
b50924c2 2685 err = ext4_handle_dirty_super(handle, inode->i_sb);
ac27a0ec 2686 } else {
617ba13b 2687 struct ext4_iloc iloc2;
ac27a0ec 2688 struct inode *i_prev =
617ba13b 2689 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
ac27a0ec 2690
498e5f24 2691 jbd_debug(4, "orphan inode %lu will point to %u\n",
ac27a0ec 2692 i_prev->i_ino, ino_next);
617ba13b 2693 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
d745a8c2
JK		 2694 if (err) {
2695 mutex_unlock(&sbi->s_orphan_lock);
ac27a0ec 2696 goto out_brelse;
d745a8c2 2697 }
ac27a0ec 2698 NEXT_ORPHAN(i_prev) = ino_next;
617ba13b 2699 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
d745a8c2 2700 mutex_unlock(&sbi->s_orphan_lock);
ac27a0ec
DK		 2701 }
2702 if (err)
2703 goto out_brelse;
2704 NEXT_ORPHAN(inode) = 0;
617ba13b 2705 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
ac27a0ec 2706out_err:
617ba13b 2707 ext4_std_error(inode->i_sb, err);
ac27a0ec
DK		 2708 return err;
2709
2710out_brelse:
2711 brelse(iloc.bh);
2712 goto out_err;
2713}
2714
af5bc92d 2715static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
ac27a0ec
DK		 2716{
2717 int retval;
af5bc92d
TT		 2718 struct inode *inode;
2719 struct buffer_head *bh;
2720 struct ext4_dir_entry_2 *de;
8dcfaad2 2721 handle_t *handle = NULL;
ac27a0ec
DK		 2722
2723 /* Initialize quotas before so that eventual writes go in
2724 * separate transaction */
871a2931
CH		 2725 dquot_initialize(dir);
2726 dquot_initialize(dentry->d_inode);
907f4554 2727
ac27a0ec 2728 retval = -ENOENT;
32f7f22c 2729 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
ac27a0ec
DK		 2730 if (!bh)
2731 goto end_rmdir;
2732
ac27a0ec
DK		 2733 inode = dentry->d_inode;
2734
2735 retval = -EIO;
2736 if (le32_to_cpu(de->inode) != inode->i_ino)
2737 goto end_rmdir;
2738
2739 retval = -ENOTEMPTY;
af5bc92d 2740 if (!empty_dir(inode))
ac27a0ec
DK		 2741 goto end_rmdir;
2742
8dcfaad2 2743 handle = ext4_journal_start(dir, EXT4_HT_DIR,
64044abf 2744 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
8dcfaad2
TT		 2745 if (IS_ERR(handle)) {
2746 retval = PTR_ERR(handle);
2747 handle = NULL;
2748 goto end_rmdir;
2749 }
2750
2751 if (IS_DIRSYNC(dir))
2752 ext4_handle_sync(handle);
2753
617ba13b 2754 retval = ext4_delete_entry(handle, dir, de, bh);
ac27a0ec
DK		 2755 if (retval)
2756 goto end_rmdir;
f8628a14 2757 if (!EXT4_DIR_LINK_EMPTY(inode))
12062ddd 2758 ext4_warning(inode->i_sb,
af5bc92d
TT		 2759 "empty directory has too many links (%d)",
2760 inode->i_nlink);
ac27a0ec
DK		 2761 inode->i_version++;
2762 clear_nlink(inode);
2763 /* There's no need to set i_disksize: the fact that i_nlink is
2764 * zero will ensure that the right thing happens during any
2765 * recovery. */
2766 inode->i_size = 0;
617ba13b 2767 ext4_orphan_add(handle, inode);
ef7f3835 2768 inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode);
617ba13b 2769 ext4_mark_inode_dirty(handle, inode);
f8628a14 2770 ext4_dec_count(handle, dir);
617ba13b
MC		 2771 ext4_update_dx_flag(dir);
2772 ext4_mark_inode_dirty(handle, dir);
ac27a0ec
DK		 2773
2774end_rmdir:
af5bc92d 2775 brelse(bh);
8dcfaad2
TT		 2776 if (handle)
2777 ext4_journal_stop(handle);
ac27a0ec
DK		 2778 return retval;
2779}
2780
af5bc92d 2781static int ext4_unlink(struct inode *dir, struct dentry *dentry)
ac27a0ec
DK		 2782{
2783 int retval;
af5bc92d
TT		 2784 struct inode *inode;
2785 struct buffer_head *bh;
2786 struct ext4_dir_entry_2 *de;
931b6864 2787 handle_t *handle = NULL;
ac27a0ec 2788
0562e0ba 2789 trace_ext4_unlink_enter(dir, dentry);
ac27a0ec
DK		 2790 /* Initialize quotas before so that eventual writes go
2791 * in separate transaction */
871a2931
CH		 2792 dquot_initialize(dir);
2793 dquot_initialize(dentry->d_inode);
907f4554 2794
ac27a0ec 2795 retval = -ENOENT;
32f7f22c 2796 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
ac27a0ec
DK		 2797 if (!bh)
2798 goto end_unlink;
2799
2800 inode = dentry->d_inode;
2801
2802 retval = -EIO;
2803 if (le32_to_cpu(de->inode) != inode->i_ino)
2804 goto end_unlink;
2805
931b6864 2806 handle = ext4_journal_start(dir, EXT4_HT_DIR,
64044abf 2807 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));
931b6864
TT		 2808 if (IS_ERR(handle)) {
2809 retval = PTR_ERR(handle);
2810 handle = NULL;
2811 goto end_unlink;
2812 }
2813
2814 if (IS_DIRSYNC(dir))
2815 ext4_handle_sync(handle);
2816
ac27a0ec 2817 if (!inode->i_nlink) {
12062ddd 2818 ext4_warning(inode->i_sb,
af5bc92d
TT		 2819 "Deleting nonexistent file (%lu), %d",
2820 inode->i_ino, inode->i_nlink);
bfe86848 2821 set_nlink(inode, 1);
ac27a0ec 2822 }
617ba13b 2823 retval = ext4_delete_entry(handle, dir, de, bh);
ac27a0ec
DK		 2824 if (retval)
2825 goto end_unlink;
ef7f3835 2826 dir->i_ctime = dir->i_mtime = ext4_current_time(dir);
617ba13b
MC		 2827 ext4_update_dx_flag(dir);
2828 ext4_mark_inode_dirty(handle, dir);
825f1481 2829 drop_nlink(inode);
ac27a0ec 2830 if (!inode->i_nlink)
617ba13b 2831 ext4_orphan_add(handle, inode);
ef7f3835 2832 inode->i_ctime = ext4_current_time(inode);
617ba13b 2833 ext4_mark_inode_dirty(handle, inode);
ac27a0ec
DK		 2834 retval = 0;
2835
2836end_unlink:
af5bc92d 2837 brelse(bh);
931b6864
TT		 2838 if (handle)
2839 ext4_journal_stop(handle);
0562e0ba 2840 trace_ext4_unlink_exit(dentry, retval);
ac27a0ec
DK		 2841 return retval;
2842}
2843
af5bc92d
TT		 2844static int ext4_symlink(struct inode *dir,
2845 struct dentry *dentry, const char *symname)
ac27a0ec
DK		 2846{
2847 handle_t *handle;
af5bc92d 2848 struct inode *inode;
ac27a0ec 2849 int l, err, retries = 0;
df5e6223 2850 int credits;
ac27a0ec
DK		 2851
2852 l = strlen(symname)+1;
2853 if (l > dir->i_sb->s_blocksize)
2854 return -ENAMETOOLONG;
2855
871a2931 2856 dquot_initialize(dir);
907f4554 2857
df5e6223
JK		 2858 if (l > EXT4_N_BLOCKS * 4) {
2859 /*
2860 * For non-fast symlinks, we just allocate inode and put it on
2861 * orphan list in the first transaction => we need bitmap,
8c208719
ES		 2862 * group descriptor, sb, inode block, quota blocks, and
2863 * possibly selinux xattr blocks.
df5e6223 2864 */
8c208719
ES		 2865 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2866 EXT4_XATTR_TRANS_BLOCKS;
df5e6223
JK		 2867 } else {
2868 /*
2869 * Fast symlink. We have to add entry to directory
2870 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
2871 * allocate new inode (bitmap, group descriptor, inode block,
2872 * quota blocks, sb is already counted in previous macros).
2873 */
2874 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
eb9cc7e1 2875 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
df5e6223 2876 }
ac27a0ec 2877retry:
1139575a
TT		 2878 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
2879 &dentry->d_name, 0, NULL,
2880 EXT4_HT_DIR, credits);
2881 handle = ext4_journal_current_handle();
ac27a0ec
DK		 2882 err = PTR_ERR(inode);
2883 if (IS_ERR(inode))
2884 goto out_stop;
2885
df5e6223 2886 if (l > EXT4_N_BLOCKS * 4) {
617ba13b
MC		 2887 inode->i_op = &ext4_symlink_inode_operations;
2888 ext4_set_aops(inode);
ac27a0ec 2889 /*
df5e6223
JK		 2890 * We cannot call page_symlink() with transaction started
2891 * because it calls into ext4_write_begin() which can wait
2892 * for transaction commit if we are running out of space
2893 * and thus we deadlock. So we have to stop transaction now
2894 * and restart it when symlink contents is written.
2895 *
2896 * To keep fs consistent in case of crash, we have to put inode
2897 * to orphan list in the mean time.
ac27a0ec 2898 */
df5e6223
JK		 2899 drop_nlink(inode);
2900 err = ext4_orphan_add(handle, inode);
2901 ext4_journal_stop(handle);
2902 if (err)
2903 goto err_drop_inode;
54566b2c 2904 err = __page_symlink(inode, symname, l, 1);
df5e6223
JK		 2905 if (err)
2906 goto err_drop_inode;
2907 /*
2908 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
2909 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
2910 */
9924a92a 2911 handle = ext4_journal_start(dir, EXT4_HT_DIR,
df5e6223
JK		 2912 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2913 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
2914 if (IS_ERR(handle)) {
2915 err = PTR_ERR(handle);
2916 goto err_drop_inode;
2917 }
0ce8c010 2918 set_nlink(inode, 1);
df5e6223 2919 err = ext4_orphan_del(handle, inode);
ac27a0ec 2920 if (err) {
df5e6223 2921 ext4_journal_stop(handle);
825f1481 2922 clear_nlink(inode);
df5e6223 2923 goto err_drop_inode;
ac27a0ec
DK		 2924 }
2925 } else {
e65187e6 2926 /* clear the extent format for fast symlink */
12e9b892 2927 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
617ba13b 2928 inode->i_op = &ext4_fast_symlink_inode_operations;
af5bc92d 2929 memcpy((char *)&EXT4_I(inode)->i_data, symname, l);
ac27a0ec
DK		 2930 inode->i_size = l-1;
2931 }
617ba13b
MC		 2932 EXT4_I(inode)->i_disksize = inode->i_size;
2933 err = ext4_add_nondir(handle, dentry, inode);
1139575a
TT		 2934 if (!err && IS_DIRSYNC(dir))
2935 ext4_handle_sync(handle);
2936
ac27a0ec 2937out_stop:
1139575a
TT		 2938 if (handle)
2939 ext4_journal_stop(handle);
617ba13b 2940 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2941 goto retry;
2942 return err;
df5e6223
JK		 2943err_drop_inode:
2944 unlock_new_inode(inode);
2945 iput(inode);
2946 return err;
ac27a0ec
DK		 2947}
2948
af5bc92d
TT		 2949static int ext4_link(struct dentry *old_dentry,
2950 struct inode *dir, struct dentry *dentry)
ac27a0ec
DK		 2951{
2952 handle_t *handle;
2953 struct inode *inode = old_dentry->d_inode;
2954 int err, retries = 0;
2955
b05ab1dc 2956 if (inode->i_nlink >= EXT4_LINK_MAX)
ac27a0ec 2957 return -EMLINK;
f8628a14 2958
871a2931 2959 dquot_initialize(dir);
907f4554 2960
ac27a0ec 2961retry:
9924a92a
TT		 2962 handle = ext4_journal_start(dir, EXT4_HT_DIR,
2963 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
af51a2ac 2964 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);
ac27a0ec
DK		 2965 if (IS_ERR(handle))
2966 return PTR_ERR(handle);
2967
2968 if (IS_DIRSYNC(dir))
0390131b 2969 ext4_handle_sync(handle);
ac27a0ec 2970
ef7f3835 2971 inode->i_ctime = ext4_current_time(inode);
f8628a14 2972 ext4_inc_count(handle, inode);
7de9c6ee 2973 ihold(inode);
ac27a0ec 2974
6b38e842
AV		 2975 err = ext4_add_entry(handle, dentry, inode);
2976 if (!err) {
2977 ext4_mark_inode_dirty(handle, inode);
af51a2ac
AV		 2978 /* this can happen only for tmpfile being
2979 * linked the first time
2980 */
2981 if (inode->i_nlink == 1)
2982 ext4_orphan_del(handle, inode);
6b38e842
AV		 2983 d_instantiate(dentry, inode);
2984 } else {
2985 drop_nlink(inode);
2986 iput(inode);
2987 }
617ba13b
MC		 2988 ext4_journal_stop(handle);
2989 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2990 goto retry;
2991 return err;
2992}
2993
32f7f22c
TM		 2994
2995/*
2996 * Try to find buffer head where contains the parent block.
2997 * It should be the inode block if it is inlined or the 1st block
2998 * if it is a normal dir.
2999 */
3000static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,
3001 struct inode *inode,
3002 int *retval,
3003 struct ext4_dir_entry_2 **parent_de,
3004 int *inlined)
3005{
3006 struct buffer_head *bh;
3007
3008 if (!ext4_has_inline_data(inode)) {
dc6982ff
TT		 3009 bh = ext4_read_dirblock(inode, 0, EITHER);
3010 if (IS_ERR(bh)) {
3011 *retval = PTR_ERR(bh);
32f7f22c
TM		 3012 return NULL;
3013 }
3014 *parent_de = ext4_next_entry(
3015 (struct ext4_dir_entry_2 *)bh->b_data,
3016 inode->i_sb->s_blocksize);
3017 return bh;
3018 }
3019
3020 *inlined = 1;
3021 return ext4_get_first_inline_block(inode, parent_de, retval);
3022}
ac27a0ec 3023
c0d268c3
MS		 3024struct ext4_renament {
3025 struct inode *dir;
3026 struct dentry *dentry;
3027 struct inode *inode;
bd42998a
MS		 3028 bool is_dir;
3029 int dir_nlink_delta;
c0d268c3
MS		 3030
3031 /* entry for "dentry" */
3032 struct buffer_head *bh;
3033 struct ext4_dir_entry_2 *de;
3034 int inlined;
3035
3036 /* entry for ".." in inode if it's a directory */
3037 struct buffer_head *dir_bh;
3038 struct ext4_dir_entry_2 *parent_de;
3039 int dir_inlined;
3040};
3041
bd1af145
MS		 3042static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
3043{
3044 int retval;
3045
3046 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
3047 &retval, &ent->parent_de,
3048 &ent->dir_inlined);
3049 if (!ent->dir_bh)
3050 return retval;
3051 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
3052 return -EIO;
3053 BUFFER_TRACE(ent->dir_bh, "get_write_access");
3054 return ext4_journal_get_write_access(handle, ent->dir_bh);
3055}
3056
3057static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
3058 unsigned dir_ino)
3059{
3060 int retval;
3061
3062 ent->parent_de->inode = cpu_to_le32(dir_ino);
3063 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
3064 if (!ent->dir_inlined) {
3065 if (is_dx(ent->inode)) {
3066 retval = ext4_handle_dirty_dx_node(handle,
3067 ent->inode,
3068 ent->dir_bh);
3069 } else {
3070 retval = ext4_handle_dirty_dirent_node(handle,
3071 ent->inode,
3072 ent->dir_bh);
3073 }
3074 } else {
3075 retval = ext4_mark_inode_dirty(handle, ent->inode);
3076 }
3077 if (retval) {
3078 ext4_std_error(ent->dir->i_sb, retval);
3079 return retval;
3080 }
3081 return 0;
3082}
3083
3084static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
3085 unsigned ino, unsigned file_type)
3086{
3087 int retval;
3088
3089 BUFFER_TRACE(ent->bh, "get write access");
3090 retval = ext4_journal_get_write_access(handle, ent->bh);
3091 if (retval)
3092 return retval;
3093 ent->de->inode = cpu_to_le32(ino);
3094 if (EXT4_HAS_INCOMPAT_FEATURE(ent->dir->i_sb,
3095 EXT4_FEATURE_INCOMPAT_FILETYPE))
3096 ent->de->file_type = file_type;
3097 ent->dir->i_version++;
3098 ent->dir->i_ctime = ent->dir->i_mtime =
3099 ext4_current_time(ent->dir);
3100 ext4_mark_inode_dirty(handle, ent->dir);
3101 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
3102 if (!ent->inlined) {
3103 retval = ext4_handle_dirty_dirent_node(handle,
3104 ent->dir, ent->bh);
3105 if (unlikely(retval)) {
3106 ext4_std_error(ent->dir->i_sb, retval);
3107 return retval;
3108 }
3109 }
3110 brelse(ent->bh);
3111 ent->bh = NULL;
3112
3113 return 0;
3114}
3115
3116static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
3117 const struct qstr *d_name)
3118{
3119 int retval = -ENOENT;
3120 struct buffer_head *bh;
3121 struct ext4_dir_entry_2 *de;
3122
3123 bh = ext4_find_entry(dir, d_name, &de, NULL);
3124 if (bh) {
3125 retval = ext4_delete_entry(handle, dir, de, bh);
3126 brelse(bh);
3127 }
3128 return retval;
3129}
3130
3131static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent)
3132{
3133 int retval;
3134 /*
3135 * ent->de could have moved from under us during htree split, so make
3136 * sure that we are deleting the right entry. We might also be pointing
3137 * to a stale entry in the unused part of ent->bh so just checking inum
3138 * and the name isn't enough.
3139 */
3140 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
3141 ent->de->name_len != ent->dentry->d_name.len ||
3142 strncmp(ent->de->name, ent->dentry->d_name.name,
3143 ent->de->name_len)) {
3144 retval = ext4_find_delete_entry(handle, ent->dir,
3145 &ent->dentry->d_name);
3146 } else {
3147 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
3148 if (retval == -ENOENT) {
3149 retval = ext4_find_delete_entry(handle, ent->dir,
3150 &ent->dentry->d_name);
3151 }
3152 }
3153
3154 if (retval) {
3155 ext4_warning(ent->dir->i_sb,
3156 "Deleting old file (%lu), %d, error=%d",
3157 ent->dir->i_ino, ent->dir->i_nlink, retval);
3158 }
3159}
3160
bd42998a
MS		 3161static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
3162{
3163 if (ent->dir_nlink_delta) {
3164 if (ent->dir_nlink_delta == -1)
3165 ext4_dec_count(handle, ent->dir);
3166 else
3167 ext4_inc_count(handle, ent->dir);
3168 ext4_mark_inode_dirty(handle, ent->dir);
3169 }
3170}
3171
ac27a0ec
DK		 3172/*
3173 * Anybody can rename anything with this: the permission checks are left to the
3174 * higher-level routines.
0e202704
TT		 3175 *
3176 * n.b. old_{dentry,inode) refers to the source dentry/inode
3177 * while new_{dentry,inode) refers to the destination dentry/inode
3178 * This comes from rename(const char *oldpath, const char *newpath)
ac27a0ec 3179 */
af5bc92d
TT		 3180static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
3181 struct inode *new_dir, struct dentry *new_dentry)
ac27a0ec 3182{
5b61de75 3183 handle_t *handle = NULL;
c0d268c3
MS		 3184 struct ext4_renament old = {
3185 .dir = old_dir,
3186 .dentry = old_dentry,
3187 .inode = old_dentry->d_inode,
3188 };
3189 struct ext4_renament new = {
3190 .dir = new_dir,
3191 .dentry = new_dentry,
3192 .inode = new_dentry->d_inode,
3193 };
0e202704 3194 int retval;
907f4554 3195
c0d268c3
MS		 3196 dquot_initialize(old.dir);
3197 dquot_initialize(new.dir);
ac27a0ec
DK		 3198
3199 /* Initialize quotas before so that eventual writes go
3200 * in separate transaction */
c0d268c3
MS		 3201 if (new.inode)
3202 dquot_initialize(new.inode);
ac27a0ec 3203
c0d268c3 3204 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL);
ac27a0ec
DK		 3205 /*
3206 * Check for inode number is _not_ due to possible IO errors.
3207 * We might rmdir the source, keep it as pwd of some process
3208 * and merrily kill the link to whatever was created under the
3209 * same name. Goodbye sticky bit ;-<
3210 */
ac27a0ec 3211 retval = -ENOENT;
c0d268c3 3212 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
ac27a0ec
DK		 3213 goto end_rename;
3214
c0d268c3
MS		 3215 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3216 &new.de, &new.inlined);
3217 if (new.bh) {
3218 if (!new.inode) {
3219 brelse(new.bh);
3220 new.bh = NULL;
ac27a0ec
DK		 3221 }
3222 }
c0d268c3
MS		 3223 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
3224 ext4_alloc_da_blocks(old.inode);
5b61de75 3225
c0d268c3
MS		 3226 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
3227 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
5b61de75
TT		 3228 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
3229 if (IS_ERR(handle))
3230 return PTR_ERR(handle);
3231
c0d268c3 3232 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
5b61de75
TT		 3233 ext4_handle_sync(handle);
3234
c0d268c3
MS		 3235 if (S_ISDIR(old.inode->i_mode)) {
3236 if (new.inode) {
ac27a0ec 3237 retval = -ENOTEMPTY;
c0d268c3 3238 if (!empty_dir(new.inode))
ac27a0ec 3239 goto end_rename;
0d7d5d67
MS		 3240 } else {
3241 retval = -EMLINK;
3242 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
3243 goto end_rename;
ac27a0ec 3244 }
bd1af145 3245 retval = ext4_rename_dir_prepare(handle, &old);
ef607893
AG		 3246 if (retval)
3247 goto end_rename;
ac27a0ec 3248 }
c0d268c3
MS		 3249 if (!new.bh) {
3250 retval = ext4_add_entry(handle, new.dentry, old.inode);
ac27a0ec
DK		 3251 if (retval)
3252 goto end_rename;
3253 } else {
bd1af145
MS		 3254 retval = ext4_setent(handle, &new,
3255 old.inode->i_ino, old.de->file_type);
ef607893
AG		 3256 if (retval)
3257 goto end_rename;
ac27a0ec
DK		 3258 }
3259
3260 /*
3261 * Like most other Unix systems, set the ctime for inodes on a
3262 * rename.
3263 */
c0d268c3
MS		 3264 old.inode->i_ctime = ext4_current_time(old.inode);
3265 ext4_mark_inode_dirty(handle, old.inode);
ac27a0ec
DK		 3266
3267 /*
3268 * ok, that's it
3269 */
bd1af145 3270 ext4_rename_delete(handle, &old);
ac27a0ec 3271
c0d268c3
MS		 3272 if (new.inode) {
3273 ext4_dec_count(handle, new.inode);
3274 new.inode->i_ctime = ext4_current_time(new.inode);
ac27a0ec 3275 }
c0d268c3
MS		 3276 old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir);
3277 ext4_update_dx_flag(old.dir);
3278 if (old.dir_bh) {
bd1af145
MS		 3279 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3280 if (retval)
b4097142 3281 goto end_rename;
bd1af145 3282
c0d268c3
MS		 3283 ext4_dec_count(handle, old.dir);
3284 if (new.inode) {
f8628a14 3285 /* checked empty_dir above, can't have another parent,
825f1481 3286 * ext4_dec_count() won't work for many-linked dirs */
c0d268c3 3287 clear_nlink(new.inode);
ac27a0ec 3288 } else {
c0d268c3
MS		 3289 ext4_inc_count(handle, new.dir);
3290 ext4_update_dx_flag(new.dir);
3291 ext4_mark_inode_dirty(handle, new.dir);
ac27a0ec
DK		 3292 }
3293 }
c0d268c3
MS		 3294 ext4_mark_inode_dirty(handle, old.dir);
3295 if (new.inode) {
3296 ext4_mark_inode_dirty(handle, new.inode);
3297 if (!new.inode->i_nlink)
3298 ext4_orphan_add(handle, new.inode);
ac27a0ec
DK		 3299 }
3300 retval = 0;
3301
3302end_rename:
c0d268c3
MS		 3303 brelse(old.dir_bh);
3304 brelse(old.bh);
3305 brelse(new.bh);
5b61de75
TT		 3306 if (handle)
3307 ext4_journal_stop(handle);
ac27a0ec
DK		 3308 return retval;
3309}
3310
bd42998a
MS		 3311static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
3312 struct inode *new_dir, struct dentry *new_dentry)
3313{
3314 handle_t *handle = NULL;
3315 struct ext4_renament old = {
3316 .dir = old_dir,
3317 .dentry = old_dentry,
3318 .inode = old_dentry->d_inode,
3319 };
3320 struct ext4_renament new = {
3321 .dir = new_dir,
3322 .dentry = new_dentry,
3323 .inode = new_dentry->d_inode,
3324 };
3325 u8 new_file_type;
3326 int retval;
3327
3328 dquot_initialize(old.dir);
3329 dquot_initialize(new.dir);
3330
3331 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,
3332 &old.de, &old.inlined);
3333 /*
3334 * Check for inode number is _not_ due to possible IO errors.
3335 * We might rmdir the source, keep it as pwd of some process
3336 * and merrily kill the link to whatever was created under the
3337 * same name. Goodbye sticky bit ;-<
3338 */
3339 retval = -ENOENT;
3340 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)
3341 goto end_rename;
3342
3343 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,
3344 &new.de, &new.inlined);
3345
3346 /* RENAME_EXCHANGE case: old *and* new must both exist */
3347 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)
3348 goto end_rename;
3349
3350 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
3351 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
3352 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
3353 if (IS_ERR(handle))
3354 return PTR_ERR(handle);
3355
3356 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
3357 ext4_handle_sync(handle);
3358
3359 if (S_ISDIR(old.inode->i_mode)) {
3360 old.is_dir = true;
3361 retval = ext4_rename_dir_prepare(handle, &old);
3362 if (retval)
3363 goto end_rename;
3364 }
3365 if (S_ISDIR(new.inode->i_mode)) {
3366 new.is_dir = true;
3367 retval = ext4_rename_dir_prepare(handle, &new);
3368 if (retval)
3369 goto end_rename;
3370 }
3371
3372 /*
3373 * Other than the special case of overwriting a directory, parents'
3374 * nlink only needs to be modified if this is a cross directory rename.
3375 */
3376 if (old.dir != new.dir && old.is_dir != new.is_dir) {
3377 old.dir_nlink_delta = old.is_dir ? -1 : 1;
3378 new.dir_nlink_delta = -old.dir_nlink_delta;
3379 retval = -EMLINK;
3380 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||
3381 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))
3382 goto end_rename;
3383 }
3384
3385 new_file_type = new.de->file_type;
3386 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);
3387 if (retval)
3388 goto end_rename;
3389
3390 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);
3391 if (retval)
3392 goto end_rename;
3393
3394 /*
3395 * Like most other Unix systems, set the ctime for inodes on a
3396 * rename.
3397 */
3398 old.inode->i_ctime = ext4_current_time(old.inode);
3399 new.inode->i_ctime = ext4_current_time(new.inode);
3400 ext4_mark_inode_dirty(handle, old.inode);
3401 ext4_mark_inode_dirty(handle, new.inode);
3402
3403 if (old.dir_bh) {
3404 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
3405 if (retval)
3406 goto end_rename;
3407 }
3408 if (new.dir_bh) {
3409 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);
3410 if (retval)
3411 goto end_rename;
3412 }
3413 ext4_update_dir_count(handle, &old);
3414 ext4_update_dir_count(handle, &new);
3415 retval = 0;
3416
3417end_rename:
3418 brelse(old.dir_bh);
3419 brelse(new.dir_bh);
3420 brelse(old.bh);
3421 brelse(new.bh);
3422 if (handle)
3423 ext4_journal_stop(handle);
3424 return retval;
3425}
3426
0a7c3937
MS		 3427static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
3428 struct inode *new_dir, struct dentry *new_dentry,
3429 unsigned int flags)
3430{
bd42998a 3431 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
0a7c3937
MS		 3432 return -EINVAL;
3433
bd42998a
MS		 3434 if (flags & RENAME_EXCHANGE) {
3435 return ext4_cross_rename(old_dir, old_dentry,
3436 new_dir, new_dentry);
3437 }
3438 /*
3439 * Existence checking was done by the VFS, otherwise "RENAME_NOREPLACE"
3440 * is equivalent to regular rename.
3441 */
0a7c3937
MS		 3442 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry);
3443}
3444
ac27a0ec
DK		 3445/*
3446 * directories can handle most operations...
3447 */
754661f1 3448const struct inode_operations ext4_dir_inode_operations = {
617ba13b
MC		 3449 .create = ext4_create,
3450 .lookup = ext4_lookup,
3451 .link = ext4_link,
3452 .unlink = ext4_unlink,
3453 .symlink = ext4_symlink,
3454 .mkdir = ext4_mkdir,
3455 .rmdir = ext4_rmdir,
3456 .mknod = ext4_mknod,
af51a2ac 3457 .tmpfile = ext4_tmpfile,
617ba13b 3458 .rename = ext4_rename,
0a7c3937 3459 .rename2 = ext4_rename2,
617ba13b 3460 .setattr = ext4_setattr,
ac27a0ec
DK		 3461 .setxattr = generic_setxattr,
3462 .getxattr = generic_getxattr,
617ba13b 3463 .listxattr = ext4_listxattr,
ac27a0ec 3464 .removexattr = generic_removexattr,
4e34e719 3465 .get_acl = ext4_get_acl,
64e178a7 3466 .set_acl = ext4_set_acl,
abc8746e 3467 .fiemap = ext4_fiemap,
ac27a0ec
DK		 3468};
3469
754661f1 3470const struct inode_operations ext4_special_inode_operations = {
617ba13b 3471 .setattr = ext4_setattr,
ac27a0ec
DK		 3472 .setxattr = generic_setxattr,
3473 .getxattr = generic_getxattr,
617ba13b 3474 .listxattr = ext4_listxattr,
ac27a0ec 3475 .removexattr = generic_removexattr,
4e34e719 3476 .get_acl = ext4_get_acl,
64e178a7 3477 .set_acl = ext4_set_acl,
ac27a0ec 3478};
Linux 6.x block layer and io_uring tree(s)