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ext4: let ext4_readdir handle inline data
[mirror_ubuntu-zesty-kernel.git] / fs / ext4 / namei.c
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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
DK		 50#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
51
617ba13b 52static struct buffer_head *ext4_append(handle_t *handle,
ac27a0ec 53 struct inode *inode,
725d26d3 54 ext4_lblk_t *block, int *err)
ac27a0ec
DK		 55{
56 struct buffer_head *bh;
57
df981d03
TT		 58 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&
59 ((inode->i_size >> 10) >=
60 EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) {
61 *err = -ENOSPC;
62 return NULL;
63 }
64
ac27a0ec
DK		 65 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
66
a871611b
AM		 67 bh = ext4_bread(handle, inode, *block, 1, err);
68 if (bh) {
ac27a0ec 69 inode->i_size += inode->i_sb->s_blocksize;
617ba13b 70 EXT4_I(inode)->i_disksize = inode->i_size;
a871611b
AM		 71 *err = ext4_journal_get_write_access(handle, bh);
72 if (*err) {
73 brelse(bh);
74 bh = NULL;
75 }
ac27a0ec 76 }
6d1ab10e
CM		 77 if (!bh && !(*err)) {
78 *err = -EIO;
79 ext4_error(inode->i_sb,
80 "Directory hole detected on inode %lu\n",
81 inode->i_ino);
82 }
ac27a0ec
DK		 83 return bh;
84}
85
86#ifndef assert
87#define assert(test) J_ASSERT(test)
88#endif
89
ac27a0ec
DK		 90#ifdef DX_DEBUG
91#define dxtrace(command) command
92#else
93#define dxtrace(command)
94#endif
95
96struct fake_dirent
97{
98 __le32 inode;
99 __le16 rec_len;
100 u8 name_len;
101 u8 file_type;
102};
103
104struct dx_countlimit
105{
106 __le16 limit;
107 __le16 count;
108};
109
110struct dx_entry
111{
112 __le32 hash;
113 __le32 block;
114};
115
116/*
117 * dx_root_info is laid out so that if it should somehow get overlaid by a
118 * dirent the two low bits of the hash version will be zero. Therefore, the
119 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
120 */
121
122struct dx_root
123{
124 struct fake_dirent dot;
125 char dot_name[4];
126 struct fake_dirent dotdot;
127 char dotdot_name[4];
128 struct dx_root_info
129 {
130 __le32 reserved_zero;
131 u8 hash_version;
132 u8 info_length; /* 8 */
133 u8 indirect_levels;
134 u8 unused_flags;
135 }
136 info;
137 struct dx_entry entries[0];
138};
139
140struct dx_node
141{
142 struct fake_dirent fake;
143 struct dx_entry entries[0];
144};
145
146
147struct dx_frame
148{
149 struct buffer_head *bh;
150 struct dx_entry *entries;
151 struct dx_entry *at;
152};
153
154struct dx_map_entry
155{
156 u32 hash;
ef2b02d3
ES		 157 u16 offs;
158 u16 size;
ac27a0ec
DK		 159};
160
e6153918
DW		 161/*
162 * This goes at the end of each htree block.
163 */
164struct dx_tail {
165 u32 dt_reserved;
166 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */
167};
168
725d26d3
AK		 169static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);
170static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);
af5bc92d
TT		 171static inline unsigned dx_get_hash(struct dx_entry *entry);
172static void dx_set_hash(struct dx_entry *entry, unsigned value);
173static unsigned dx_get_count(struct dx_entry *entries);
174static unsigned dx_get_limit(struct dx_entry *entries);
175static void dx_set_count(struct dx_entry *entries, unsigned value);
176static void dx_set_limit(struct dx_entry *entries, unsigned value);
177static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
178static unsigned dx_node_limit(struct inode *dir);
f702ba0f 179static struct dx_frame *dx_probe(const struct qstr *d_name,
ac27a0ec
DK		 180 struct inode *dir,
181 struct dx_hash_info *hinfo,
182 struct dx_frame *frame,
183 int *err);
af5bc92d 184static void dx_release(struct dx_frame *frames);
8bad4597 185static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
af5bc92d 186 struct dx_hash_info *hinfo, struct dx_map_entry map[]);
ac27a0ec 187static void dx_sort_map(struct dx_map_entry *map, unsigned count);
af5bc92d 188static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
3d0518f4 189 struct dx_map_entry *offsets, int count, unsigned blocksize);
8bad4597 190static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
725d26d3
AK		 191static void dx_insert_block(struct dx_frame *frame,
192 u32 hash, ext4_lblk_t block);
617ba13b 193static int ext4_htree_next_block(struct inode *dir, __u32 hash,
ac27a0ec
DK		 194 struct dx_frame *frame,
195 struct dx_frame *frames,
196 __u32 *start_hash);
f702ba0f
TT		 197static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
198 const struct qstr *d_name,
199 struct ext4_dir_entry_2 **res_dir,
200 int *err);
617ba13b 201static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
ac27a0ec
DK		 202 struct inode *inode);
203
dbe89444 204/* checksumming functions */
3c47d541
TM		 205void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
206 unsigned int blocksize)
b0336e8d
DW		 207{
208 memset(t, 0, sizeof(struct ext4_dir_entry_tail));
209 t->det_rec_len = ext4_rec_len_to_disk(
210 sizeof(struct ext4_dir_entry_tail), blocksize);
211 t->det_reserved_ft = EXT4_FT_DIR_CSUM;
212}
213
214/* Walk through a dirent block to find a checksum "dirent" at the tail */
215static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
216 struct ext4_dir_entry *de)
217{
218 struct ext4_dir_entry_tail *t;
219
220#ifdef PARANOID
221 struct ext4_dir_entry *d, *top;
222
223 d = de;
224 top = (struct ext4_dir_entry *)(((void *)de) +
225 (EXT4_BLOCK_SIZE(inode->i_sb) -
226 sizeof(struct ext4_dir_entry_tail)));
227 while (d < top && d->rec_len)
228 d = (struct ext4_dir_entry *)(((void *)d) +
229 le16_to_cpu(d->rec_len));
230
231 if (d != top)
232 return NULL;
233
234 t = (struct ext4_dir_entry_tail *)d;
235#else
236 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
237#endif
238
239 if (t->det_reserved_zero1 ||
240 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
241 t->det_reserved_zero2 ||
242 t->det_reserved_ft != EXT4_FT_DIR_CSUM)
243 return NULL;
244
245 return t;
246}
247
248static __le32 ext4_dirent_csum(struct inode *inode,
249 struct ext4_dir_entry *dirent, int size)
250{
251 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
252 struct ext4_inode_info *ei = EXT4_I(inode);
253 __u32 csum;
254
255 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
256 return cpu_to_le32(csum);
257}
258
dffe9d8d
TT		 259static void warn_no_space_for_csum(struct inode *inode)
260{
261 ext4_warning(inode->i_sb, "no space in directory inode %lu leaf for "
262 "checksum. Please run e2fsck -D.", inode->i_ino);
263}
264
b0336e8d
DW		 265int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
266{
267 struct ext4_dir_entry_tail *t;
268
269 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
270 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
271 return 1;
272
273 t = get_dirent_tail(inode, dirent);
274 if (!t) {
dffe9d8d 275 warn_no_space_for_csum(inode);
b0336e8d
DW		 276 return 0;
277 }
278
279 if (t->det_checksum != ext4_dirent_csum(inode, dirent,
280 (void *)t - (void *)dirent))
281 return 0;
282
283 return 1;
284}
285
286static void ext4_dirent_csum_set(struct inode *inode,
287 struct ext4_dir_entry *dirent)
288{
289 struct ext4_dir_entry_tail *t;
290
291 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
292 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
293 return;
294
295 t = get_dirent_tail(inode, dirent);
296 if (!t) {
dffe9d8d 297 warn_no_space_for_csum(inode);
b0336e8d
DW		 298 return;
299 }
300
301 t->det_checksum = ext4_dirent_csum(inode, dirent,
302 (void *)t - (void *)dirent);
303}
304
3c47d541
TM		 305int ext4_handle_dirty_dirent_node(handle_t *handle,
306 struct inode *inode,
307 struct buffer_head *bh)
b0336e8d
DW		 308{
309 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
310 return ext4_handle_dirty_metadata(handle, inode, bh);
311}
312
dbe89444
DW		 313static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
314 struct ext4_dir_entry *dirent,
315 int *offset)
316{
317 struct ext4_dir_entry *dp;
318 struct dx_root_info *root;
319 int count_offset;
320
321 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
322 count_offset = 8;
323 else if (le16_to_cpu(dirent->rec_len) == 12) {
324 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
325 if (le16_to_cpu(dp->rec_len) !=
326 EXT4_BLOCK_SIZE(inode->i_sb) - 12)
327 return NULL;
328 root = (struct dx_root_info *)(((void *)dp + 12));
329 if (root->reserved_zero ||
330 root->info_length != sizeof(struct dx_root_info))
331 return NULL;
332 count_offset = 32;
333 } else
334 return NULL;
335
336 if (offset)
337 *offset = count_offset;
338 return (struct dx_countlimit *)(((void *)dirent) + count_offset);
339}
340
341static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,
342 int count_offset, int count, struct dx_tail *t)
343{
344 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
345 struct ext4_inode_info *ei = EXT4_I(inode);
346 __u32 csum, old_csum;
347 int size;
348
349 size = count_offset + (count * sizeof(struct dx_entry));
350 old_csum = t->dt_checksum;
351 t->dt_checksum = 0;
352 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);
353 csum = ext4_chksum(sbi, csum, (__u8 *)t, sizeof(struct dx_tail));
354 t->dt_checksum = old_csum;
355
356 return cpu_to_le32(csum);
357}
358
359static int ext4_dx_csum_verify(struct inode *inode,
360 struct ext4_dir_entry *dirent)
361{
362 struct dx_countlimit *c;
363 struct dx_tail *t;
364 int count_offset, limit, count;
365
366 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
367 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
368 return 1;
369
370 c = get_dx_countlimit(inode, dirent, &count_offset);
371 if (!c) {
372 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
373 return 1;
374 }
375 limit = le16_to_cpu(c->limit);
376 count = le16_to_cpu(c->count);
377 if (count_offset + (limit * sizeof(struct dx_entry)) >
378 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
dffe9d8d 379 warn_no_space_for_csum(inode);
dbe89444
DW		 380 return 1;
381 }
382 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
383
384 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,
385 count, t))
386 return 0;
387 return 1;
388}
389
390static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)
391{
392 struct dx_countlimit *c;
393 struct dx_tail *t;
394 int count_offset, limit, count;
395
396 if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
397 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
398 return;
399
400 c = get_dx_countlimit(inode, dirent, &count_offset);
401 if (!c) {
402 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");
403 return;
404 }
405 limit = le16_to_cpu(c->limit);
406 count = le16_to_cpu(c->count);
407 if (count_offset + (limit * sizeof(struct dx_entry)) >
408 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {
dffe9d8d 409 warn_no_space_for_csum(inode);
dbe89444
DW		 410 return;
411 }
412 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);
413
414 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);
415}
416
417static inline int ext4_handle_dirty_dx_node(handle_t *handle,
418 struct inode *inode,
419 struct buffer_head *bh)
420{
421 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
422 return ext4_handle_dirty_metadata(handle, inode, bh);
423}
424
f795e140
LZ		 425/*
426 * p is at least 6 bytes before the end of page
427 */
428static inline struct ext4_dir_entry_2 *
3d0518f4 429ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
f795e140
LZ		 430{
431 return (struct ext4_dir_entry_2 *)((char *)p +
3d0518f4 432 ext4_rec_len_from_disk(p->rec_len, blocksize));
f795e140
LZ		 433}
434
ac27a0ec
DK		 435/*
436 * Future: use high four bits of block for coalesce-on-delete flags
437 * Mask them off for now.
438 */
439
725d26d3 440static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)
ac27a0ec
DK		 441{
442 return le32_to_cpu(entry->block) & 0x00ffffff;
443}
444
725d26d3 445static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)
ac27a0ec
DK		 446{
447 entry->block = cpu_to_le32(value);
448}
449
af5bc92d 450static inline unsigned dx_get_hash(struct dx_entry *entry)
ac27a0ec
DK		 451{
452 return le32_to_cpu(entry->hash);
453}
454
af5bc92d 455static inline void dx_set_hash(struct dx_entry *entry, unsigned value)
ac27a0ec
DK		 456{
457 entry->hash = cpu_to_le32(value);
458}
459
af5bc92d 460static inline unsigned dx_get_count(struct dx_entry *entries)
ac27a0ec
DK		 461{
462 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
463}
464
af5bc92d 465static inline unsigned dx_get_limit(struct dx_entry *entries)
ac27a0ec
DK		 466{
467 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
468}
469
af5bc92d 470static inline void dx_set_count(struct dx_entry *entries, unsigned value)
ac27a0ec
DK		 471{
472 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
473}
474
af5bc92d 475static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
ac27a0ec
DK		 476{
477 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
478}
479
af5bc92d 480static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
ac27a0ec 481{
617ba13b
MC		 482 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
483 EXT4_DIR_REC_LEN(2) - infosize;
dbe89444
DW		 484
485 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
486 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
487 entry_space -= sizeof(struct dx_tail);
d9c769b7 488 return entry_space / sizeof(struct dx_entry);
ac27a0ec
DK		 489}
490
af5bc92d 491static inline unsigned dx_node_limit(struct inode *dir)
ac27a0ec 492{
617ba13b 493 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
dbe89444
DW		 494
495 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
496 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
497 entry_space -= sizeof(struct dx_tail);
d9c769b7 498 return entry_space / sizeof(struct dx_entry);
ac27a0ec
DK		 499}
500
501/*
502 * Debug
503 */
504#ifdef DX_DEBUG
4776004f 505static void dx_show_index(char * label, struct dx_entry *entries)
ac27a0ec 506{
63f57933 507 int i, n = dx_get_count (entries);
4776004f 508 printk(KERN_DEBUG "%s index ", label);
63f57933 509 for (i = 0; i < n; i++) {
4776004f 510 printk("%x->%lu ", i ? dx_get_hash(entries + i) :
725d26d3 511 0, (unsigned long)dx_get_block(entries + i));
63f57933
AM		 512 }
513 printk("\n");
ac27a0ec
DK		 514}
515
516struct stats
517{
518 unsigned names;
519 unsigned space;
520 unsigned bcount;
521};
522
617ba13b 523static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
ac27a0ec
DK		 524 int size, int show_names)
525{
526 unsigned names = 0, space = 0;
527 char *base = (char *) de;
528 struct dx_hash_info h = *hinfo;
529
530 printk("names: ");
531 while ((char *) de < base + size)
532 {
533 if (de->inode)
534 {
535 if (show_names)
536 {
537 int len = de->name_len;
538 char *name = de->name;
539 while (len--) printk("%c", *name++);
617ba13b 540 ext4fs_dirhash(de->name, de->name_len, &h);
ac27a0ec 541 printk(":%x.%u ", h.hash,
265c6a0f 542 (unsigned) ((char *) de - base));
ac27a0ec 543 }
617ba13b 544 space += EXT4_DIR_REC_LEN(de->name_len);
ac27a0ec
DK		 545 names++;
546 }
3d0518f4 547 de = ext4_next_entry(de, size);
ac27a0ec
DK		 548 }
549 printk("(%i)\n", names);
550 return (struct stats) { names, space, 1 };
551}
552
553struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
554 struct dx_entry *entries, int levels)
555{
556 unsigned blocksize = dir->i_sb->s_blocksize;
af5bc92d 557 unsigned count = dx_get_count(entries), names = 0, space = 0, i;
ac27a0ec
DK		 558 unsigned bcount = 0;
559 struct buffer_head *bh;
560 int err;
561 printk("%i indexed blocks...\n", count);
562 for (i = 0; i < count; i++, entries++)
563 {
725d26d3
AK		 564 ext4_lblk_t block = dx_get_block(entries);
565 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;
ac27a0ec
DK		 566 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
567 struct stats stats;
568 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
617ba13b 569 if (!(bh = ext4_bread (NULL,dir, block, 0,&err))) continue;
ac27a0ec
DK		 570 stats = levels?
571 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
617ba13b 572 dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
ac27a0ec
DK		 573 names += stats.names;
574 space += stats.space;
575 bcount += stats.bcount;
af5bc92d 576 brelse(bh);
ac27a0ec
DK		 577 }
578 if (bcount)
60e6679e 579 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",
4776004f
TT		 580 levels ? "" : " ", names, space/bcount,
581 (space/bcount)*100/blocksize);
ac27a0ec
DK		 582 return (struct stats) { names, space, bcount};
583}
584#endif /* DX_DEBUG */
585
586/*
587 * Probe for a directory leaf block to search.
588 *
589 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
590 * error in the directory index, and the caller should fall back to
591 * searching the directory normally. The callers of dx_probe **MUST**
592 * check for this error code, and make sure it never gets reflected
593 * back to userspace.
594 */
595static struct dx_frame *
f702ba0f 596dx_probe(const struct qstr *d_name, struct inode *dir,
ac27a0ec
DK		 597 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
598{
599 unsigned count, indirect;
600 struct dx_entry *at, *entries, *p, *q, *m;
601 struct dx_root *root;
602 struct buffer_head *bh;
603 struct dx_frame *frame = frame_in;
604 u32 hash;
605
606 frame->bh = NULL;
6d1ab10e
CM		 607 if (!(bh = ext4_bread(NULL, dir, 0, 0, err))) {
608 if (*err == 0)
609 *err = ERR_BAD_DX_DIR;
ac27a0ec 610 goto fail;
6d1ab10e 611 }
ac27a0ec
DK		 612 root = (struct dx_root *) bh->b_data;
613 if (root->info.hash_version != DX_HASH_TEA &&
614 root->info.hash_version != DX_HASH_HALF_MD4 &&
615 root->info.hash_version != DX_HASH_LEGACY) {
12062ddd 616 ext4_warning(dir->i_sb, "Unrecognised inode hash code %d",
ac27a0ec
DK		 617 root->info.hash_version);
618 brelse(bh);
619 *err = ERR_BAD_DX_DIR;
620 goto fail;
621 }
622 hinfo->hash_version = root->info.hash_version;
f99b2589
TT		 623 if (hinfo->hash_version <= DX_HASH_TEA)
624 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
617ba13b 625 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
f702ba0f
TT		 626 if (d_name)
627 ext4fs_dirhash(d_name->name, d_name->len, hinfo);
ac27a0ec
DK		 628 hash = hinfo->hash;
629
630 if (root->info.unused_flags & 1) {
12062ddd 631 ext4_warning(dir->i_sb, "Unimplemented inode hash flags: %#06x",
ac27a0ec
DK		 632 root->info.unused_flags);
633 brelse(bh);
634 *err = ERR_BAD_DX_DIR;
635 goto fail;
636 }
637
638 if ((indirect = root->info.indirect_levels) > 1) {
12062ddd 639 ext4_warning(dir->i_sb, "Unimplemented inode hash depth: %#06x",
ac27a0ec
DK		 640 root->info.indirect_levels);
641 brelse(bh);
642 *err = ERR_BAD_DX_DIR;
643 goto fail;
644 }
645
dbe89444
DW		 646 if (!buffer_verified(bh) &&
647 !ext4_dx_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data)) {
648 ext4_warning(dir->i_sb, "Root failed checksum");
649 brelse(bh);
650 *err = ERR_BAD_DX_DIR;
651 goto fail;
652 }
653 set_buffer_verified(bh);
654
ac27a0ec
DK		 655 entries = (struct dx_entry *) (((char *)&root->info) +
656 root->info.info_length);
3d82abae
ES		 657
658 if (dx_get_limit(entries) != dx_root_limit(dir,
659 root->info.info_length)) {
12062ddd 660 ext4_warning(dir->i_sb, "dx entry: limit != root limit");
3d82abae
ES		 661 brelse(bh);
662 *err = ERR_BAD_DX_DIR;
663 goto fail;
664 }
665
af5bc92d 666 dxtrace(printk("Look up %x", hash));
ac27a0ec
DK		 667 while (1)
668 {
669 count = dx_get_count(entries);
3d82abae 670 if (!count || count > dx_get_limit(entries)) {
12062ddd 671 ext4_warning(dir->i_sb,
3d82abae
ES		 672 "dx entry: no count or count > limit");
673 brelse(bh);
674 *err = ERR_BAD_DX_DIR;
675 goto fail2;
676 }
677
ac27a0ec
DK		 678 p = entries + 1;
679 q = entries + count - 1;
680 while (p <= q)
681 {
682 m = p + (q - p)/2;
683 dxtrace(printk("."));
684 if (dx_get_hash(m) > hash)
685 q = m - 1;
686 else
687 p = m + 1;
688 }
689
690 if (0) // linear search cross check
691 {
692 unsigned n = count - 1;
693 at = entries;
694 while (n--)
695 {
696 dxtrace(printk(","));
697 if (dx_get_hash(++at) > hash)
698 {
699 at--;
700 break;
701 }
702 }
703 assert (at == p - 1);
704 }
705
706 at = p - 1;
707 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
708 frame->bh = bh;
709 frame->entries = entries;
710 frame->at = at;
711 if (!indirect--) return frame;
6d1ab10e
CM		 712 if (!(bh = ext4_bread(NULL, dir, dx_get_block(at), 0, err))) {
713 if (!(*err))
714 *err = ERR_BAD_DX_DIR;
ac27a0ec 715 goto fail2;
6d1ab10e 716 }
ac27a0ec 717 at = entries = ((struct dx_node *) bh->b_data)->entries;
dbe89444
DW		 718
719 if (!buffer_verified(bh) &&
720 !ext4_dx_csum_verify(dir,
721 (struct ext4_dir_entry *)bh->b_data)) {
722 ext4_warning(dir->i_sb, "Node failed checksum");
723 brelse(bh);
724 *err = ERR_BAD_DX_DIR;
725 goto fail;
726 }
727 set_buffer_verified(bh);
728
3d82abae 729 if (dx_get_limit(entries) != dx_node_limit (dir)) {
12062ddd 730 ext4_warning(dir->i_sb,
3d82abae
ES		 731 "dx entry: limit != node limit");
732 brelse(bh);
733 *err = ERR_BAD_DX_DIR;
734 goto fail2;
735 }
ac27a0ec 736 frame++;
3d82abae 737 frame->bh = NULL;
ac27a0ec
DK		 738 }
739fail2:
740 while (frame >= frame_in) {
741 brelse(frame->bh);
742 frame--;
743 }
744fail:
3d82abae 745 if (*err == ERR_BAD_DX_DIR)
12062ddd 746 ext4_warning(dir->i_sb,
9ee49302 747 "Corrupt dir inode %lu, running e2fsck is "
3d82abae 748 "recommended.", dir->i_ino);
ac27a0ec
DK		 749 return NULL;
750}
751
752static void dx_release (struct dx_frame *frames)
753{
754 if (frames[0].bh == NULL)
755 return;
756
757 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
758 brelse(frames[1].bh);
759 brelse(frames[0].bh);
760}
761
762/*
763 * This function increments the frame pointer to search the next leaf
764 * block, and reads in the necessary intervening nodes if the search
765 * should be necessary. Whether or not the search is necessary is
766 * controlled by the hash parameter. If the hash value is even, then
767 * the search is only continued if the next block starts with that
768 * hash value. This is used if we are searching for a specific file.
769 *
770 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
771 *
772 * This function returns 1 if the caller should continue to search,
773 * or 0 if it should not. If there is an error reading one of the
774 * index blocks, it will a negative error code.
775 *
776 * If start_hash is non-null, it will be filled in with the starting
777 * hash of the next page.
778 */
617ba13b 779static int ext4_htree_next_block(struct inode *dir, __u32 hash,
ac27a0ec
DK		 780 struct dx_frame *frame,
781 struct dx_frame *frames,
782 __u32 *start_hash)
783{
784 struct dx_frame *p;
785 struct buffer_head *bh;
786 int err, num_frames = 0;
787 __u32 bhash;
788
789 p = frame;
790 /*
791 * Find the next leaf page by incrementing the frame pointer.
792 * If we run out of entries in the interior node, loop around and
793 * increment pointer in the parent node. When we break out of
794 * this loop, num_frames indicates the number of interior
795 * nodes need to be read.
796 */
797 while (1) {
798 if (++(p->at) < p->entries + dx_get_count(p->entries))
799 break;
800 if (p == frames)
801 return 0;
802 num_frames++;
803 p--;
804 }
805
806 /*
807 * If the hash is 1, then continue only if the next page has a
808 * continuation hash of any value. This is used for readdir
809 * handling. Otherwise, check to see if the hash matches the
810 * desired contiuation hash. If it doesn't, return since
811 * there's no point to read in the successive index pages.
812 */
813 bhash = dx_get_hash(p->at);
814 if (start_hash)
815 *start_hash = bhash;
816 if ((hash & 1) == 0) {
817 if ((bhash & ~1) != hash)
818 return 0;
819 }
820 /*
821 * If the hash is HASH_NB_ALWAYS, we always go to the next
822 * block so no check is necessary
823 */
824 while (num_frames--) {
617ba13b 825 if (!(bh = ext4_bread(NULL, dir, dx_get_block(p->at),
6d1ab10e
CM		 826 0, &err))) {
827 if (!err) {
828 ext4_error(dir->i_sb,
829 "Directory hole detected on inode %lu\n",
830 dir->i_ino);
831 return -EIO;
832 }
ac27a0ec 833 return err; /* Failure */
6d1ab10e 834 }
dbe89444
DW		 835
836 if (!buffer_verified(bh) &&
837 !ext4_dx_csum_verify(dir,
838 (struct ext4_dir_entry *)bh->b_data)) {
839 ext4_warning(dir->i_sb, "Node failed checksum");
840 return -EIO;
841 }
842 set_buffer_verified(bh);
843
ac27a0ec 844 p++;
af5bc92d 845 brelse(p->bh);
ac27a0ec
DK		 846 p->bh = bh;
847 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
848 }
849 return 1;
850}
851
852
ac27a0ec
DK		 853/*
854 * This function fills a red-black tree with information from a
855 * directory block. It returns the number directory entries loaded
856 * into the tree. If there is an error it is returned in err.
857 */
858static int htree_dirblock_to_tree(struct file *dir_file,
725d26d3 859 struct inode *dir, ext4_lblk_t block,
ac27a0ec
DK		 860 struct dx_hash_info *hinfo,
861 __u32 start_hash, __u32 start_minor_hash)
862{
863 struct buffer_head *bh;
617ba13b 864 struct ext4_dir_entry_2 *de, *top;
90b0a973 865 int err = 0, count = 0;
ac27a0ec 866
725d26d3
AK		 867 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
868 (unsigned long)block));
6d1ab10e
CM		 869 if (!(bh = ext4_bread(NULL, dir, block, 0, &err))) {
870 if (!err) {
871 err = -EIO;
872 ext4_error(dir->i_sb,
873 "Directory hole detected on inode %lu\n",
874 dir->i_ino);
875 }
ac27a0ec 876 return err;
6d1ab10e 877 }
ac27a0ec 878
b0336e8d
DW		 879 if (!buffer_verified(bh) &&
880 !ext4_dirent_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data))
881 return -EIO;
882 set_buffer_verified(bh);
883
617ba13b
MC		 884 de = (struct ext4_dir_entry_2 *) bh->b_data;
885 top = (struct ext4_dir_entry_2 *) ((char *) de +
ac27a0ec 886 dir->i_sb->s_blocksize -
617ba13b 887 EXT4_DIR_REC_LEN(0));
3d0518f4 888 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
f7c21177 889 if (ext4_check_dir_entry(dir, NULL, de, bh,
226ba972 890 bh->b_data, bh->b_size,
cad3f007
TT		 891 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
892 + ((char *)de - bh->b_data))) {
e6c40211
ES		 893 /* On error, skip the f_pos to the next block. */
894 dir_file->f_pos = (dir_file->f_pos |
895 (dir->i_sb->s_blocksize - 1)) + 1;
af5bc92d 896 brelse(bh);
e6c40211
ES		 897 return count;
898 }
617ba13b 899 ext4fs_dirhash(de->name, de->name_len, hinfo);
ac27a0ec
DK		 900 if ((hinfo->hash < start_hash) ||
901 ((hinfo->hash == start_hash) &&
902 (hinfo->minor_hash < start_minor_hash)))
903 continue;
904 if (de->inode == 0)
905 continue;
617ba13b 906 if ((err = ext4_htree_store_dirent(dir_file,
ac27a0ec
DK		 907 hinfo->hash, hinfo->minor_hash, de)) != 0) {
908 brelse(bh);
909 return err;
910 }
911 count++;
912 }
913 brelse(bh);
914 return count;
915}
916
917
918/*
919 * This function fills a red-black tree with information from a
920 * directory. We start scanning the directory in hash order, starting
921 * at start_hash and start_minor_hash.
922 *
923 * This function returns the number of entries inserted into the tree,
924 * or a negative error code.
925 */
617ba13b 926int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
ac27a0ec
DK		 927 __u32 start_minor_hash, __u32 *next_hash)
928{
929 struct dx_hash_info hinfo;
617ba13b 930 struct ext4_dir_entry_2 *de;
ac27a0ec
DK		 931 struct dx_frame frames[2], *frame;
932 struct inode *dir;
725d26d3 933 ext4_lblk_t block;
ac27a0ec 934 int count = 0;
725d26d3 935 int ret, err;
ac27a0ec
DK		 936 __u32 hashval;
937
60e6679e 938 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
4776004f 939 start_hash, start_minor_hash));
9d549890 940 dir = dir_file->f_path.dentry->d_inode;
12e9b892 941 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {
617ba13b 942 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
f99b2589
TT		 943 if (hinfo.hash_version <= DX_HASH_TEA)
944 hinfo.hash_version +=
945 EXT4_SB(dir->i_sb)->s_hash_unsigned;
617ba13b 946 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
ac27a0ec
DK		 947 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
948 start_hash, start_minor_hash);
949 *next_hash = ~0;
950 return count;
951 }
952 hinfo.hash = start_hash;
953 hinfo.minor_hash = 0;
f702ba0f 954 frame = dx_probe(NULL, dir, &hinfo, frames, &err);
ac27a0ec
DK		 955 if (!frame)
956 return err;
957
958 /* Add '.' and '..' from the htree header */
959 if (!start_hash && !start_minor_hash) {
617ba13b
MC		 960 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
961 if ((err = ext4_htree_store_dirent(dir_file, 0, 0, de)) != 0)
ac27a0ec
DK		 962 goto errout;
963 count++;
964 }
965 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
617ba13b 966 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
3d0518f4 967 de = ext4_next_entry(de, dir->i_sb->s_blocksize);
617ba13b 968 if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
ac27a0ec
DK		 969 goto errout;
970 count++;
971 }
972
973 while (1) {
974 block = dx_get_block(frame->at);
975 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
976 start_hash, start_minor_hash);
977 if (ret < 0) {
978 err = ret;
979 goto errout;
980 }
981 count += ret;
982 hashval = ~0;
617ba13b 983 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
ac27a0ec
DK		 984 frame, frames, &hashval);
985 *next_hash = hashval;
986 if (ret < 0) {
987 err = ret;
988 goto errout;
989 }
990 /*
991 * Stop if: (a) there are no more entries, or
992 * (b) we have inserted at least one entry and the
993 * next hash value is not a continuation
994 */
995 if ((ret == 0) ||
996 (count && ((hashval & 1) == 0)))
997 break;
998 }
999 dx_release(frames);
4776004f
TT		 1000 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "
1001 "next hash: %x\n", count, *next_hash));
ac27a0ec
DK		 1002 return count;
1003errout:
1004 dx_release(frames);
1005 return (err);
1006}
1007
1008
1009/*
1010 * Directory block splitting, compacting
1011 */
1012
ef2b02d3
ES		 1013/*
1014 * Create map of hash values, offsets, and sizes, stored at end of block.
1015 * Returns number of entries mapped.
1016 */
8bad4597
TT		 1017static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
1018 struct dx_hash_info *hinfo,
1019 struct dx_map_entry *map_tail)
ac27a0ec
DK		 1020{
1021 int count = 0;
1022 char *base = (char *) de;
1023 struct dx_hash_info h = *hinfo;
1024
8bad4597 1025 while ((char *) de < base + blocksize) {
ac27a0ec 1026 if (de->name_len && de->inode) {
617ba13b 1027 ext4fs_dirhash(de->name, de->name_len, &h);
ac27a0ec
DK		 1028 map_tail--;
1029 map_tail->hash = h.hash;
9aee2286 1030 map_tail->offs = ((char *) de - base)>>2;
ef2b02d3 1031 map_tail->size = le16_to_cpu(de->rec_len);
ac27a0ec
DK		 1032 count++;
1033 cond_resched();
1034 }
1035 /* XXX: do we need to check rec_len == 0 case? -Chris */
3d0518f4 1036 de = ext4_next_entry(de, blocksize);
ac27a0ec
DK		 1037 }
1038 return count;
1039}
1040
ef2b02d3 1041/* Sort map by hash value */
ac27a0ec
DK		 1042static void dx_sort_map (struct dx_map_entry *map, unsigned count)
1043{
63f57933
AM		 1044 struct dx_map_entry *p, *q, *top = map + count - 1;
1045 int more;
1046 /* Combsort until bubble sort doesn't suck */
1047 while (count > 2) {
1048 count = count*10/13;
1049 if (count - 9 < 2) /* 9, 10 -> 11 */
1050 count = 11;
1051 for (p = top, q = p - count; q >= map; p--, q--)
1052 if (p->hash < q->hash)
1053 swap(*p, *q);
1054 }
1055 /* Garden variety bubble sort */
1056 do {
1057 more = 0;
1058 q = top;
1059 while (q-- > map) {
1060 if (q[1].hash >= q[0].hash)
ac27a0ec 1061 continue;
63f57933
AM		 1062 swap(*(q+1), *q);
1063 more = 1;
ac27a0ec
DK		 1064 }
1065 } while(more);
1066}
1067
725d26d3 1068static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
ac27a0ec
DK		 1069{
1070 struct dx_entry *entries = frame->entries;
1071 struct dx_entry *old = frame->at, *new = old + 1;
1072 int count = dx_get_count(entries);
1073
1074 assert(count < dx_get_limit(entries));
1075 assert(old < entries + count);
1076 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
1077 dx_set_hash(new, hash);
1078 dx_set_block(new, block);
1079 dx_set_count(entries, count + 1);
1080}
ac27a0ec 1081
ac27a0ec 1082/*
617ba13b 1083 * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
ac27a0ec 1084 *
617ba13b 1085 * `len <= EXT4_NAME_LEN' is guaranteed by caller.
ac27a0ec
DK		 1086 * `de != NULL' is guaranteed by caller.
1087 */
617ba13b
MC		 1088static inline int ext4_match (int len, const char * const name,
1089 struct ext4_dir_entry_2 * de)
ac27a0ec
DK		 1090{
1091 if (len != de->name_len)
1092 return 0;
1093 if (!de->inode)
1094 return 0;
1095 return !memcmp(name, de->name, len);
1096}
1097
1098/*
1099 * Returns 0 if not found, -1 on failure, and 1 on success
1100 */
af5bc92d 1101static inline int search_dirblock(struct buffer_head *bh,
ac27a0ec 1102 struct inode *dir,
f702ba0f 1103 const struct qstr *d_name,
498e5f24 1104 unsigned int offset,
617ba13b 1105 struct ext4_dir_entry_2 ** res_dir)
ac27a0ec 1106{
617ba13b 1107 struct ext4_dir_entry_2 * de;
ac27a0ec
DK		 1108 char * dlimit;
1109 int de_len;
f702ba0f
TT		 1110 const char *name = d_name->name;
1111 int namelen = d_name->len;
ac27a0ec 1112
617ba13b 1113 de = (struct ext4_dir_entry_2 *) bh->b_data;
ac27a0ec
DK		 1114 dlimit = bh->b_data + dir->i_sb->s_blocksize;
1115 while ((char *) de < dlimit) {
1116 /* this code is executed quadratically often */
1117 /* do minimal checking `by hand' */
1118
1119 if ((char *) de + namelen <= dlimit &&
617ba13b 1120 ext4_match (namelen, name, de)) {
ac27a0ec 1121 /* found a match - just to be sure, do a full check */
226ba972
TM		 1122 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data,
1123 bh->b_size, offset))
ac27a0ec
DK		 1124 return -1;
1125 *res_dir = de;
1126 return 1;
1127 }
1128 /* prevent looping on a bad block */
3d0518f4
WY		 1129 de_len = ext4_rec_len_from_disk(de->rec_len,
1130 dir->i_sb->s_blocksize);
ac27a0ec
DK		 1131 if (de_len <= 0)
1132 return -1;
1133 offset += de_len;
617ba13b 1134 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
ac27a0ec
DK		 1135 }
1136 return 0;
1137}
1138
c6af8803
DW		 1139static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,
1140 struct ext4_dir_entry *de)
1141{
1142 struct super_block *sb = dir->i_sb;
1143
1144 if (!is_dx(dir))
1145 return 0;
1146 if (block == 0)
1147 return 1;
1148 if (de->inode == 0 &&
1149 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==
1150 sb->s_blocksize)
1151 return 1;
1152 return 0;
1153}
ac27a0ec
DK		 1154
1155/*
617ba13b 1156 * ext4_find_entry()
ac27a0ec
DK		 1157 *
1158 * finds an entry in the specified directory with the wanted name. It
1159 * returns the cache buffer in which the entry was found, and the entry
1160 * itself (as a parameter - res_dir). It does NOT read the inode of the
1161 * entry - you'll have to do that yourself if you want to.
1162 *
1163 * The returned buffer_head has ->b_count elevated. The caller is expected
1164 * to brelse() it when appropriate.
1165 */
f702ba0f
TT		 1166static struct buffer_head * ext4_find_entry (struct inode *dir,
1167 const struct qstr *d_name,
617ba13b 1168 struct ext4_dir_entry_2 ** res_dir)
ac27a0ec 1169{
af5bc92d
TT		 1170 struct super_block *sb;
1171 struct buffer_head *bh_use[NAMEI_RA_SIZE];
1172 struct buffer_head *bh, *ret = NULL;
725d26d3 1173 ext4_lblk_t start, block, b;
8941ec8b 1174 const u8 *name = d_name->name;
ac27a0ec
DK		 1175 int ra_max = 0; /* Number of bh's in the readahead
1176 buffer, bh_use[] */
1177 int ra_ptr = 0; /* Current index into readahead
1178 buffer */
1179 int num = 0;
725d26d3
AK		 1180 ext4_lblk_t nblocks;
1181 int i, err;
ac27a0ec 1182 int namelen;
ac27a0ec
DK		 1183
1184 *res_dir = NULL;
1185 sb = dir->i_sb;
f702ba0f 1186 namelen = d_name->len;
617ba13b 1187 if (namelen > EXT4_NAME_LEN)
ac27a0ec 1188 return NULL;
8941ec8b 1189 if ((namelen <= 2) && (name[0] == '.') &&
6d5c3aa8 1190 (name[1] == '.' || name[1] == '\0')) {
8941ec8b
TT		 1191 /*
1192 * "." or ".." will only be in the first block
1193 * NFS may look up ".."; "." should be handled by the VFS
1194 */
1195 block = start = 0;
1196 nblocks = 1;
1197 goto restart;
1198 }
ac27a0ec 1199 if (is_dx(dir)) {
f702ba0f 1200 bh = ext4_dx_find_entry(dir, d_name, res_dir, &err);
ac27a0ec
DK		 1201 /*
1202 * On success, or if the error was file not found,
1203 * return. Otherwise, fall back to doing a search the
1204 * old fashioned way.
1205 */
1206 if (bh || (err != ERR_BAD_DX_DIR))
1207 return bh;
4776004f
TT		 1208 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "
1209 "falling back\n"));
ac27a0ec 1210 }
617ba13b
MC		 1211 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
1212 start = EXT4_I(dir)->i_dir_start_lookup;
ac27a0ec
DK		 1213 if (start >= nblocks)
1214 start = 0;
1215 block = start;
1216restart:
1217 do {
1218 /*
1219 * We deal with the read-ahead logic here.
1220 */
1221 if (ra_ptr >= ra_max) {
1222 /* Refill the readahead buffer */
1223 ra_ptr = 0;
1224 b = block;
1225 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
1226 /*
1227 * Terminate if we reach the end of the
1228 * directory and must wrap, or if our
1229 * search has finished at this block.
1230 */
1231 if (b >= nblocks || (num && block == start)) {
1232 bh_use[ra_max] = NULL;
1233 break;
1234 }
1235 num++;
617ba13b 1236 bh = ext4_getblk(NULL, dir, b++, 0, &err);
ac27a0ec
DK		 1237 bh_use[ra_max] = bh;
1238 if (bh)
65299a3b
CH		 1239 ll_rw_block(READ | REQ_META | REQ_PRIO,
1240 1, &bh);
ac27a0ec
DK		 1241 }
1242 }
1243 if ((bh = bh_use[ra_ptr++]) == NULL)
1244 goto next;
1245 wait_on_buffer(bh);
1246 if (!buffer_uptodate(bh)) {
1247 /* read error, skip block & hope for the best */
24676da4
TT		 1248 EXT4_ERROR_INODE(dir, "reading directory lblock %lu",
1249 (unsigned long) block);
ac27a0ec
DK		 1250 brelse(bh);
1251 goto next;
1252 }
b0336e8d 1253 if (!buffer_verified(bh) &&
c6af8803
DW		 1254 !is_dx_internal_node(dir, block,
1255 (struct ext4_dir_entry *)bh->b_data) &&
b0336e8d
DW		 1256 !ext4_dirent_csum_verify(dir,
1257 (struct ext4_dir_entry *)bh->b_data)) {
1258 EXT4_ERROR_INODE(dir, "checksumming directory "
1259 "block %lu", (unsigned long)block);
1260 brelse(bh);
1261 goto next;
1262 }
1263 set_buffer_verified(bh);
f702ba0f 1264 i = search_dirblock(bh, dir, d_name,
617ba13b 1265 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
ac27a0ec 1266 if (i == 1) {
617ba13b 1267 EXT4_I(dir)->i_dir_start_lookup = block;
ac27a0ec
DK		 1268 ret = bh;
1269 goto cleanup_and_exit;
1270 } else {
1271 brelse(bh);
1272 if (i < 0)
1273 goto cleanup_and_exit;
1274 }
1275 next:
1276 if (++block >= nblocks)
1277 block = 0;
1278 } while (block != start);
1279
1280 /*
1281 * If the directory has grown while we were searching, then
1282 * search the last part of the directory before giving up.
1283 */
1284 block = nblocks;
617ba13b 1285 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
ac27a0ec
DK		 1286 if (block < nblocks) {
1287 start = 0;
1288 goto restart;
1289 }
1290
1291cleanup_and_exit:
1292 /* Clean up the read-ahead blocks */
1293 for (; ra_ptr < ra_max; ra_ptr++)
af5bc92d 1294 brelse(bh_use[ra_ptr]);
ac27a0ec
DK		 1295 return ret;
1296}
1297
f702ba0f 1298static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct qstr *d_name,
617ba13b 1299 struct ext4_dir_entry_2 **res_dir, int *err)
ac27a0ec 1300{
8941ec8b 1301 struct super_block * sb = dir->i_sb;
ac27a0ec 1302 struct dx_hash_info hinfo;
ac27a0ec 1303 struct dx_frame frames[2], *frame;
ac27a0ec 1304 struct buffer_head *bh;
725d26d3 1305 ext4_lblk_t block;
ac27a0ec 1306 int retval;
ac27a0ec 1307
8941ec8b
TT		 1308 if (!(frame = dx_probe(d_name, dir, &hinfo, frames, err)))
1309 return NULL;
ac27a0ec
DK		 1310 do {
1311 block = dx_get_block(frame->at);
6d1ab10e
CM		 1312 if (!(bh = ext4_bread(NULL, dir, block, 0, err))) {
1313 if (!(*err)) {
1314 *err = -EIO;
1315 ext4_error(dir->i_sb,
1316 "Directory hole detected on inode %lu\n",
1317 dir->i_ino);
1318 }
ac27a0ec 1319 goto errout;
6d1ab10e 1320 }
f3b35f06 1321
b0336e8d
DW		 1322 if (!buffer_verified(bh) &&
1323 !ext4_dirent_csum_verify(dir,
1324 (struct ext4_dir_entry *)bh->b_data)) {
1325 EXT4_ERROR_INODE(dir, "checksumming directory "
1326 "block %lu", (unsigned long)block);
1327 brelse(bh);
1328 *err = -EIO;
1329 goto errout;
1330 }
1331 set_buffer_verified(bh);
7845c049
TT		 1332 retval = search_dirblock(bh, dir, d_name,
1333 block << EXT4_BLOCK_SIZE_BITS(sb),
1334 res_dir);
1335 if (retval == 1) { /* Success! */
1336 dx_release(frames);
1337 return bh;
ac27a0ec 1338 }
af5bc92d 1339 brelse(bh);
7845c049
TT		 1340 if (retval == -1) {
1341 *err = ERR_BAD_DX_DIR;
1342 goto errout;
1343 }
1344
ac27a0ec 1345 /* Check to see if we should continue to search */
8941ec8b 1346 retval = ext4_htree_next_block(dir, hinfo.hash, frame,
ac27a0ec
DK		 1347 frames, NULL);
1348 if (retval < 0) {
12062ddd 1349 ext4_warning(sb,
ac27a0ec
DK		 1350 "error reading index page in directory #%lu",
1351 dir->i_ino);
1352 *err = retval;
1353 goto errout;
1354 }
1355 } while (retval == 1);
1356
1357 *err = -ENOENT;
1358errout:
265c6a0f 1359 dxtrace(printk(KERN_DEBUG "%s not found\n", d_name->name));
ac27a0ec
DK		 1360 dx_release (frames);
1361 return NULL;
1362}
ac27a0ec 1363
00cd8dd3 1364static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
ac27a0ec 1365{
af5bc92d
TT		 1366 struct inode *inode;
1367 struct ext4_dir_entry_2 *de;
1368 struct buffer_head *bh;
ac27a0ec 1369
617ba13b 1370 if (dentry->d_name.len > EXT4_NAME_LEN)
ac27a0ec
DK		 1371 return ERR_PTR(-ENAMETOOLONG);
1372
f702ba0f 1373 bh = ext4_find_entry(dir, &dentry->d_name, &de);
ac27a0ec
DK		 1374 inode = NULL;
1375 if (bh) {
498e5f24 1376 __u32 ino = le32_to_cpu(de->inode);
af5bc92d 1377 brelse(bh);
617ba13b 1378 if (!ext4_valid_inum(dir->i_sb, ino)) {
24676da4 1379 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);
1d1fe1ee 1380 return ERR_PTR(-EIO);
a6c15c2b 1381 }
7e936b73
AD		 1382 if (unlikely(ino == dir->i_ino)) {
1383 EXT4_ERROR_INODE(dir, "'%.*s' linked to parent dir",
1384 dentry->d_name.len,
1385 dentry->d_name.name);
1386 return ERR_PTR(-EIO);
1387 }
1d1fe1ee 1388 inode = ext4_iget(dir->i_sb, ino);
a9049376
AV		 1389 if (inode == ERR_PTR(-ESTALE)) {
1390 EXT4_ERROR_INODE(dir,
1391 "deleted inode referenced: %u",
1392 ino);
1393 return ERR_PTR(-EIO);
e6f009b0 1394 }
ac27a0ec
DK		 1395 }
1396 return d_splice_alias(inode, dentry);
1397}
1398
1399
617ba13b 1400struct dentry *ext4_get_parent(struct dentry *child)
ac27a0ec 1401{
498e5f24 1402 __u32 ino;
26fe5750 1403 static const struct qstr dotdot = QSTR_INIT("..", 2);
617ba13b 1404 struct ext4_dir_entry_2 * de;
ac27a0ec
DK		 1405 struct buffer_head *bh;
1406
f702ba0f 1407 bh = ext4_find_entry(child->d_inode, &dotdot, &de);
ac27a0ec
DK		 1408 if (!bh)
1409 return ERR_PTR(-ENOENT);
1410 ino = le32_to_cpu(de->inode);
1411 brelse(bh);
1412
617ba13b 1413 if (!ext4_valid_inum(child->d_inode->i_sb, ino)) {
24676da4
TT		 1414 EXT4_ERROR_INODE(child->d_inode,
1415 "bad parent inode number: %u", ino);
1d1fe1ee 1416 return ERR_PTR(-EIO);
a6c15c2b
VA		 1417 }
1418
44003728 1419 return d_obtain_alias(ext4_iget(child->d_inode->i_sb, ino));
ac27a0ec
DK		 1420}
1421
1422#define S_SHIFT 12
617ba13b
MC		 1423static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
1424 [S_IFREG >> S_SHIFT] = EXT4_FT_REG_FILE,
1425 [S_IFDIR >> S_SHIFT] = EXT4_FT_DIR,
1426 [S_IFCHR >> S_SHIFT] = EXT4_FT_CHRDEV,
1427 [S_IFBLK >> S_SHIFT] = EXT4_FT_BLKDEV,
1428 [S_IFIFO >> S_SHIFT] = EXT4_FT_FIFO,
1429 [S_IFSOCK >> S_SHIFT] = EXT4_FT_SOCK,
1430 [S_IFLNK >> S_SHIFT] = EXT4_FT_SYMLINK,
ac27a0ec
DK		 1431};
1432
617ba13b
MC		 1433static inline void ext4_set_de_type(struct super_block *sb,
1434 struct ext4_dir_entry_2 *de,
ac27a0ec 1435 umode_t mode) {
617ba13b
MC		 1436 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
1437 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
ac27a0ec
DK		 1438}
1439
ef2b02d3
ES		 1440/*
1441 * Move count entries from end of map between two memory locations.
1442 * Returns pointer to last entry moved.
1443 */
617ba13b 1444static struct ext4_dir_entry_2 *
3d0518f4
WY		 1445dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
1446 unsigned blocksize)
ac27a0ec
DK		 1447{
1448 unsigned rec_len = 0;
1449
1450 while (count--) {
60e6679e 1451 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
9aee2286 1452 (from + (map->offs<<2));
617ba13b 1453 rec_len = EXT4_DIR_REC_LEN(de->name_len);
ac27a0ec 1454 memcpy (to, de, rec_len);
617ba13b 1455 ((struct ext4_dir_entry_2 *) to)->rec_len =
3d0518f4 1456 ext4_rec_len_to_disk(rec_len, blocksize);
ac27a0ec
DK		 1457 de->inode = 0;
1458 map++;
1459 to += rec_len;
1460 }
617ba13b 1461 return (struct ext4_dir_entry_2 *) (to - rec_len);
ac27a0ec
DK		 1462}
1463
ef2b02d3
ES		 1464/*
1465 * Compact each dir entry in the range to the minimal rec_len.
1466 * Returns pointer to last entry in range.
1467 */
8bad4597 1468static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
ac27a0ec 1469{
617ba13b 1470 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
ac27a0ec
DK		 1471 unsigned rec_len = 0;
1472
1473 prev = to = de;
8bad4597 1474 while ((char*)de < base + blocksize) {
3d0518f4 1475 next = ext4_next_entry(de, blocksize);
ac27a0ec 1476 if (de->inode && de->name_len) {
617ba13b 1477 rec_len = EXT4_DIR_REC_LEN(de->name_len);
ac27a0ec
DK		 1478 if (de > to)
1479 memmove(to, de, rec_len);
3d0518f4 1480 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
ac27a0ec 1481 prev = to;
617ba13b 1482 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
ac27a0ec
DK		 1483 }
1484 de = next;
1485 }
1486 return prev;
1487}
1488
ef2b02d3
ES		 1489/*
1490 * Split a full leaf block to make room for a new dir entry.
1491 * Allocate a new block, and move entries so that they are approx. equally full.
1492 * Returns pointer to de in block into which the new entry will be inserted.
1493 */
617ba13b 1494static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
ac27a0ec
DK		 1495 struct buffer_head **bh,struct dx_frame *frame,
1496 struct dx_hash_info *hinfo, int *error)
1497{
1498 unsigned blocksize = dir->i_sb->s_blocksize;
1499 unsigned count, continued;
1500 struct buffer_head *bh2;
725d26d3 1501 ext4_lblk_t newblock;
ac27a0ec
DK		 1502 u32 hash2;
1503 struct dx_map_entry *map;
1504 char *data1 = (*bh)->b_data, *data2;
59e315b4 1505 unsigned split, move, size;
617ba13b 1506 struct ext4_dir_entry_2 *de = NULL, *de2;
b0336e8d
DW		 1507 struct ext4_dir_entry_tail *t;
1508 int csum_size = 0;
59e315b4 1509 int err = 0, i;
ac27a0ec 1510
b0336e8d
DW		 1511 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
1512 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1513 csum_size = sizeof(struct ext4_dir_entry_tail);
1514
fedee54d 1515 bh2 = ext4_append (handle, dir, &newblock, &err);
ac27a0ec
DK		 1516 if (!(bh2)) {
1517 brelse(*bh);
1518 *bh = NULL;
1519 goto errout;
1520 }
1521
1522 BUFFER_TRACE(*bh, "get_write_access");
617ba13b 1523 err = ext4_journal_get_write_access(handle, *bh);
fedee54d
DM		 1524 if (err)
1525 goto journal_error;
1526
ac27a0ec 1527 BUFFER_TRACE(frame->bh, "get_write_access");
617ba13b 1528 err = ext4_journal_get_write_access(handle, frame->bh);
ac27a0ec
DK		 1529 if (err)
1530 goto journal_error;
1531
1532 data2 = bh2->b_data;
1533
1534 /* create map in the end of data2 block */
1535 map = (struct dx_map_entry *) (data2 + blocksize);
af5bc92d 1536 count = dx_make_map((struct ext4_dir_entry_2 *) data1,
ac27a0ec
DK		 1537 blocksize, hinfo, map);
1538 map -= count;
af5bc92d 1539 dx_sort_map(map, count);
ef2b02d3
ES		 1540 /* Split the existing block in the middle, size-wise */
1541 size = 0;
1542 move = 0;
1543 for (i = count-1; i >= 0; i--) {
1544 /* is more than half of this entry in 2nd half of the block? */
1545 if (size + map[i].size/2 > blocksize/2)
1546 break;
1547 size += map[i].size;
1548 move++;
1549 }
1550 /* map index at which we will split */
1551 split = count - move;
ac27a0ec
DK		 1552 hash2 = map[split].hash;
1553 continued = hash2 == map[split - 1].hash;
725d26d3
AK		 1554 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",
1555 (unsigned long)dx_get_block(frame->at),
1556 hash2, split, count-split));
ac27a0ec
DK		 1557
1558 /* Fancy dance to stay within two buffers */
3d0518f4 1559 de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize);
af5bc92d 1560 de = dx_pack_dirents(data1, blocksize);
b0336e8d
DW		 1561 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1562 (char *) de,
3d0518f4 1563 blocksize);
b0336e8d
DW		 1564 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -
1565 (char *) de2,
3d0518f4 1566 blocksize);
b0336e8d
DW		 1567 if (csum_size) {
1568 t = EXT4_DIRENT_TAIL(data2, blocksize);
1569 initialize_dirent_tail(t, blocksize);
1570
1571 t = EXT4_DIRENT_TAIL(data1, blocksize);
1572 initialize_dirent_tail(t, blocksize);
1573 }
1574
617ba13b
MC		 1575 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
1576 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
ac27a0ec
DK		 1577
1578 /* Which block gets the new entry? */
1579 if (hinfo->hash >= hash2)
1580 {
1581 swap(*bh, bh2);
1582 de = de2;
1583 }
af5bc92d 1584 dx_insert_block(frame, hash2 + continued, newblock);
b0336e8d 1585 err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
ac27a0ec
DK		 1586 if (err)
1587 goto journal_error;
dbe89444 1588 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
ac27a0ec
DK		 1589 if (err)
1590 goto journal_error;
af5bc92d
TT		 1591 brelse(bh2);
1592 dxtrace(dx_show_index("frame", frame->entries));
ac27a0ec 1593 return de;
fedee54d
DM		 1594
1595journal_error:
1596 brelse(*bh);
1597 brelse(bh2);
1598 *bh = NULL;
1599 ext4_std_error(dir->i_sb, err);
1600errout:
1601 *error = err;
1602 return NULL;
ac27a0ec 1603}
ac27a0ec 1604
978fef91
TM		 1605int ext4_find_dest_de(struct inode *dir, struct inode *inode,
1606 struct buffer_head *bh,
1607 void *buf, int buf_size,
1608 const char *name, int namelen,
1609 struct ext4_dir_entry_2 **dest_de)
1610{
1611 struct ext4_dir_entry_2 *de;
1612 unsigned short reclen = EXT4_DIR_REC_LEN(namelen);
1613 int nlen, rlen;
1614 unsigned int offset = 0;
1615 char *top;
1616
1617 de = (struct ext4_dir_entry_2 *)buf;
1618 top = buf + buf_size - reclen;
1619 while ((char *) de <= top) {
1620 if (ext4_check_dir_entry(dir, NULL, de, bh,
1621 buf, buf_size, offset))
1622 return -EIO;
1623 if (ext4_match(namelen, name, de))
1624 return -EEXIST;
1625 nlen = EXT4_DIR_REC_LEN(de->name_len);
1626 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1627 if ((de->inode ? rlen - nlen : rlen) >= reclen)
1628 break;
1629 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
1630 offset += rlen;
1631 }
1632 if ((char *) de > top)
1633 return -ENOSPC;
1634
1635 *dest_de = de;
1636 return 0;
1637}
1638
1639void ext4_insert_dentry(struct inode *inode,
1640 struct ext4_dir_entry_2 *de,
1641 int buf_size,
1642 const char *name, int namelen)
1643{
1644
1645 int nlen, rlen;
1646
1647 nlen = EXT4_DIR_REC_LEN(de->name_len);
1648 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
1649 if (de->inode) {
1650 struct ext4_dir_entry_2 *de1 =
1651 (struct ext4_dir_entry_2 *)((char *)de + nlen);
1652 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);
1653 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);
1654 de = de1;
1655 }
1656 de->file_type = EXT4_FT_UNKNOWN;
1657 de->inode = cpu_to_le32(inode->i_ino);
1658 ext4_set_de_type(inode->i_sb, de, inode->i_mode);
1659 de->name_len = namelen;
1660 memcpy(de->name, name, namelen);
1661}
ac27a0ec
DK		 1662/*
1663 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1664 * it points to a directory entry which is guaranteed to be large
1665 * enough for new directory entry. If de is NULL, then
1666 * add_dirent_to_buf will attempt search the directory block for
1667 * space. It will return -ENOSPC if no space is available, and -EIO
1668 * and -EEXIST if directory entry already exists.
ac27a0ec
DK		 1669 */
1670static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
617ba13b 1671 struct inode *inode, struct ext4_dir_entry_2 *de,
af5bc92d 1672 struct buffer_head *bh)
ac27a0ec
DK		 1673{
1674 struct inode *dir = dentry->d_parent->d_inode;
1675 const char *name = dentry->d_name.name;
1676 int namelen = dentry->d_name.len;
3d0518f4 1677 unsigned int blocksize = dir->i_sb->s_blocksize;
ac27a0ec 1678 unsigned short reclen;
b0336e8d 1679 int csum_size = 0;
978fef91 1680 int err;
b0336e8d
DW		 1681
1682 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1683 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1684 csum_size = sizeof(struct ext4_dir_entry_tail);
ac27a0ec 1685
617ba13b 1686 reclen = EXT4_DIR_REC_LEN(namelen);
ac27a0ec 1687 if (!de) {
978fef91
TM		 1688 err = ext4_find_dest_de(dir, inode,
1689 bh, bh->b_data, blocksize - csum_size,
1690 name, namelen, &de);
1691 if (err)
1692 return err;
ac27a0ec
DK		 1693 }
1694 BUFFER_TRACE(bh, "get_write_access");
617ba13b 1695 err = ext4_journal_get_write_access(handle, bh);
ac27a0ec 1696 if (err) {
617ba13b 1697 ext4_std_error(dir->i_sb, err);
ac27a0ec
DK		 1698 return err;
1699 }
1700
1701 /* By now the buffer is marked for journaling */
978fef91
TM		 1702 ext4_insert_dentry(inode, de, blocksize, name, namelen);
1703
ac27a0ec
DK		 1704 /*
1705 * XXX shouldn't update any times until successful
1706 * completion of syscall, but too many callers depend
1707 * on this.
1708 *
1709 * XXX similarly, too many callers depend on
617ba13b 1710 * ext4_new_inode() setting the times, but error
ac27a0ec
DK		 1711 * recovery deletes the inode, so the worst that can
1712 * happen is that the times are slightly out of date
1713 * and/or different from the directory change time.
1714 */
ef7f3835 1715 dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
617ba13b 1716 ext4_update_dx_flag(dir);
ac27a0ec 1717 dir->i_version++;
617ba13b 1718 ext4_mark_inode_dirty(handle, dir);
0390131b 1719 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
b0336e8d 1720 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
ac27a0ec 1721 if (err)
617ba13b 1722 ext4_std_error(dir->i_sb, err);
ac27a0ec
DK		 1723 return 0;
1724}
1725
ac27a0ec
DK		 1726/*
1727 * This converts a one block unindexed directory to a 3 block indexed
1728 * directory, and adds the dentry to the indexed directory.
1729 */
1730static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1731 struct inode *inode, struct buffer_head *bh)
1732{
1733 struct inode *dir = dentry->d_parent->d_inode;
1734 const char *name = dentry->d_name.name;
1735 int namelen = dentry->d_name.len;
1736 struct buffer_head *bh2;
1737 struct dx_root *root;
1738 struct dx_frame frames[2], *frame;
1739 struct dx_entry *entries;
617ba13b 1740 struct ext4_dir_entry_2 *de, *de2;
b0336e8d 1741 struct ext4_dir_entry_tail *t;
ac27a0ec
DK		 1742 char *data1, *top;
1743 unsigned len;
1744 int retval;
1745 unsigned blocksize;
1746 struct dx_hash_info hinfo;
725d26d3 1747 ext4_lblk_t block;
ac27a0ec 1748 struct fake_dirent *fde;
b0336e8d
DW		 1749 int csum_size = 0;
1750
1751 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1752 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1753 csum_size = sizeof(struct ext4_dir_entry_tail);
ac27a0ec
DK		 1754
1755 blocksize = dir->i_sb->s_blocksize;
e6b8bc09 1756 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));
617ba13b 1757 retval = ext4_journal_get_write_access(handle, bh);
ac27a0ec 1758 if (retval) {
617ba13b 1759 ext4_std_error(dir->i_sb, retval);
ac27a0ec
DK		 1760 brelse(bh);
1761 return retval;
1762 }
1763 root = (struct dx_root *) bh->b_data;
1764
e6b8bc09
TT		 1765 /* The 0th block becomes the root, move the dirents out */
1766 fde = &root->dotdot;
1767 de = (struct ext4_dir_entry_2 *)((char *)fde +
3d0518f4 1768 ext4_rec_len_from_disk(fde->rec_len, blocksize));
e6b8bc09 1769 if ((char *) de >= (((char *) root) + blocksize)) {
24676da4 1770 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'");
e6b8bc09
TT		 1771 brelse(bh);
1772 return -EIO;
1773 }
b0336e8d 1774 len = ((char *) root) + (blocksize - csum_size) - (char *) de;
e6b8bc09
TT		 1775
1776 /* Allocate new block for the 0th block's dirents */
af5bc92d 1777 bh2 = ext4_append(handle, dir, &block, &retval);
ac27a0ec
DK		 1778 if (!(bh2)) {
1779 brelse(bh);
1780 return retval;
1781 }
12e9b892 1782 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);
ac27a0ec
DK		 1783 data1 = bh2->b_data;
1784
ac27a0ec 1785 memcpy (data1, de, len);
617ba13b 1786 de = (struct ext4_dir_entry_2 *) data1;
ac27a0ec 1787 top = data1 + len;
3d0518f4 1788 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
ac27a0ec 1789 de = de2;
b0336e8d
DW		 1790 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -
1791 (char *) de,
3d0518f4 1792 blocksize);
b0336e8d
DW		 1793
1794 if (csum_size) {
1795 t = EXT4_DIRENT_TAIL(data1, blocksize);
1796 initialize_dirent_tail(t, blocksize);
1797 }
1798
ac27a0ec 1799 /* Initialize the root; the dot dirents already exist */
617ba13b 1800 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
3d0518f4
WY		 1801 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
1802 blocksize);
ac27a0ec
DK		 1803 memset (&root->info, 0, sizeof(root->info));
1804 root->info.info_length = sizeof(root->info);
617ba13b 1805 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
ac27a0ec 1806 entries = root->entries;
af5bc92d
TT		 1807 dx_set_block(entries, 1);
1808 dx_set_count(entries, 1);
1809 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));
ac27a0ec
DK		 1810
1811 /* Initialize as for dx_probe */
1812 hinfo.hash_version = root->info.hash_version;
f99b2589
TT		 1813 if (hinfo.hash_version <= DX_HASH_TEA)
1814 hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;
617ba13b
MC		 1815 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1816 ext4fs_dirhash(name, namelen, &hinfo);
ac27a0ec
DK		 1817 frame = frames;
1818 frame->entries = entries;
1819 frame->at = entries;
1820 frame->bh = bh;
1821 bh = bh2;
6976a6f2 1822
dbe89444 1823 ext4_handle_dirty_dx_node(handle, dir, frame->bh);
b0336e8d 1824 ext4_handle_dirty_dirent_node(handle, dir, bh);
6976a6f2 1825
ac27a0ec 1826 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
7ad8e4e6
JK		 1827 if (!de) {
1828 /*
1829 * Even if the block split failed, we have to properly write
1830 * out all the changes we did so far. Otherwise we can end up
1831 * with corrupted filesystem.
1832 */
1833 ext4_mark_inode_dirty(handle, dir);
7ad8e4e6 1834 dx_release(frames);
ac27a0ec 1835 return retval;
7ad8e4e6
JK		 1836 }
1837 dx_release(frames);
ac27a0ec 1838
2de770a4
TT		 1839 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1840 brelse(bh);
1841 return retval;
ac27a0ec 1842}
ac27a0ec
DK		 1843
1844/*
617ba13b 1845 * ext4_add_entry()
ac27a0ec
DK		 1846 *
1847 * adds a file entry to the specified directory, using the same
617ba13b 1848 * semantics as ext4_find_entry(). It returns NULL if it failed.
ac27a0ec
DK		 1849 *
1850 * NOTE!! The inode part of 'de' is left at 0 - which means you
1851 * may not sleep between calling this and putting something into
1852 * the entry, as someone else might have used it while you slept.
1853 */
af5bc92d
TT		 1854static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
1855 struct inode *inode)
ac27a0ec
DK		 1856{
1857 struct inode *dir = dentry->d_parent->d_inode;
af5bc92d 1858 struct buffer_head *bh;
617ba13b 1859 struct ext4_dir_entry_2 *de;
b0336e8d 1860 struct ext4_dir_entry_tail *t;
af5bc92d 1861 struct super_block *sb;
ac27a0ec 1862 int retval;
ac27a0ec 1863 int dx_fallback=0;
ac27a0ec 1864 unsigned blocksize;
725d26d3 1865 ext4_lblk_t block, blocks;
b0336e8d
DW		 1866 int csum_size = 0;
1867
1868 if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1869 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1870 csum_size = sizeof(struct ext4_dir_entry_tail);
ac27a0ec
DK		 1871
1872 sb = dir->i_sb;
1873 blocksize = sb->s_blocksize;
1874 if (!dentry->d_name.len)
1875 return -EINVAL;
3c47d541
TM		 1876
1877 if (ext4_has_inline_data(dir)) {
1878 retval = ext4_try_add_inline_entry(handle, dentry, inode);
1879 if (retval < 0)
1880 return retval;
1881 if (retval == 1) {
1882 retval = 0;
1883 return retval;
1884 }
1885 }
1886
ac27a0ec 1887 if (is_dx(dir)) {
617ba13b 1888 retval = ext4_dx_add_entry(handle, dentry, inode);
ac27a0ec
DK		 1889 if (!retval || (retval != ERR_BAD_DX_DIR))
1890 return retval;
12e9b892 1891 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
ac27a0ec 1892 dx_fallback++;
617ba13b 1893 ext4_mark_inode_dirty(handle, dir);
ac27a0ec 1894 }
ac27a0ec 1895 blocks = dir->i_size >> sb->s_blocksize_bits;
498e5f24 1896 for (block = 0; block < blocks; block++) {
6d1ab10e
CM		 1897 if (!(bh = ext4_bread(handle, dir, block, 0, &retval))) {
1898 if (!retval) {
1899 retval = -EIO;
1900 ext4_error(inode->i_sb,
1901 "Directory hole detected on inode %lu\n",
1902 inode->i_ino);
1903 }
ac27a0ec 1904 return retval;
6d1ab10e 1905 }
b0336e8d
DW		 1906 if (!buffer_verified(bh) &&
1907 !ext4_dirent_csum_verify(dir,
1908 (struct ext4_dir_entry *)bh->b_data))
1909 return -EIO;
1910 set_buffer_verified(bh);
ac27a0ec 1911 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
2de770a4
TT		 1912 if (retval != -ENOSPC) {
1913 brelse(bh);
ac27a0ec 1914 return retval;
2de770a4 1915 }
ac27a0ec 1916
ac27a0ec 1917 if (blocks == 1 && !dx_fallback &&
1e424a34
TT		 1918 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
1919 return make_indexed_dir(handle, dentry, inode, bh);
ac27a0ec
DK		 1920 brelse(bh);
1921 }
617ba13b 1922 bh = ext4_append(handle, dir, &block, &retval);
ac27a0ec
DK		 1923 if (!bh)
1924 return retval;
617ba13b 1925 de = (struct ext4_dir_entry_2 *) bh->b_data;
ac27a0ec 1926 de->inode = 0;
b0336e8d
DW		 1927 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);
1928
1929 if (csum_size) {
1930 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);
1931 initialize_dirent_tail(t, blocksize);
1932 }
1933
2de770a4
TT		 1934 retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
1935 brelse(bh);
14ece102
FM		 1936 if (retval == 0)
1937 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);
2de770a4 1938 return retval;
ac27a0ec
DK		 1939}
1940
ac27a0ec
DK		 1941/*
1942 * Returns 0 for success, or a negative error value
1943 */
617ba13b 1944static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
ac27a0ec
DK		 1945 struct inode *inode)
1946{
1947 struct dx_frame frames[2], *frame;
1948 struct dx_entry *entries, *at;
1949 struct dx_hash_info hinfo;
af5bc92d 1950 struct buffer_head *bh;
ac27a0ec 1951 struct inode *dir = dentry->d_parent->d_inode;
af5bc92d 1952 struct super_block *sb = dir->i_sb;
617ba13b 1953 struct ext4_dir_entry_2 *de;
ac27a0ec
DK		 1954 int err;
1955
f702ba0f 1956 frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err);
ac27a0ec
DK		 1957 if (!frame)
1958 return err;
1959 entries = frame->entries;
1960 at = frame->at;
1961
6d1ab10e
CM		 1962 if (!(bh = ext4_bread(handle, dir, dx_get_block(frame->at), 0, &err))) {
1963 if (!err) {
1964 err = -EIO;
1965 ext4_error(dir->i_sb,
1966 "Directory hole detected on inode %lu\n",
1967 dir->i_ino);
1968 }
ac27a0ec 1969 goto cleanup;
6d1ab10e 1970 }
ac27a0ec 1971
b0336e8d
DW		 1972 if (!buffer_verified(bh) &&
1973 !ext4_dirent_csum_verify(dir, (struct ext4_dir_entry *)bh->b_data))
1974 goto journal_error;
1975 set_buffer_verified(bh);
1976
ac27a0ec 1977 BUFFER_TRACE(bh, "get_write_access");
617ba13b 1978 err = ext4_journal_get_write_access(handle, bh);
ac27a0ec
DK		 1979 if (err)
1980 goto journal_error;
1981
1982 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
2de770a4 1983 if (err != -ENOSPC)
ac27a0ec 1984 goto cleanup;
ac27a0ec
DK		 1985
1986 /* Block full, should compress but for now just split */
4776004f 1987 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",
ac27a0ec
DK		 1988 dx_get_count(entries), dx_get_limit(entries)));
1989 /* Need to split index? */
1990 if (dx_get_count(entries) == dx_get_limit(entries)) {
725d26d3 1991 ext4_lblk_t newblock;
ac27a0ec
DK		 1992 unsigned icount = dx_get_count(entries);
1993 int levels = frame - frames;
1994 struct dx_entry *entries2;
1995 struct dx_node *node2;
1996 struct buffer_head *bh2;
1997
1998 if (levels && (dx_get_count(frames->entries) ==
1999 dx_get_limit(frames->entries))) {
12062ddd 2000 ext4_warning(sb, "Directory index full!");
ac27a0ec
DK		 2001 err = -ENOSPC;
2002 goto cleanup;
2003 }
617ba13b 2004 bh2 = ext4_append (handle, dir, &newblock, &err);
ac27a0ec
DK		 2005 if (!(bh2))
2006 goto cleanup;
2007 node2 = (struct dx_node *)(bh2->b_data);
2008 entries2 = node2->entries;
1f7bebb9 2009 memset(&node2->fake, 0, sizeof(struct fake_dirent));
3d0518f4
WY		 2010 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
2011 sb->s_blocksize);
ac27a0ec 2012 BUFFER_TRACE(frame->bh, "get_write_access");
617ba13b 2013 err = ext4_journal_get_write_access(handle, frame->bh);
ac27a0ec
DK		 2014 if (err)
2015 goto journal_error;
2016 if (levels) {
2017 unsigned icount1 = icount/2, icount2 = icount - icount1;
2018 unsigned hash2 = dx_get_hash(entries + icount1);
4776004f
TT		 2019 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",
2020 icount1, icount2));
ac27a0ec
DK		 2021
2022 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
617ba13b 2023 err = ext4_journal_get_write_access(handle,
ac27a0ec
DK		 2024 frames[0].bh);
2025 if (err)
2026 goto journal_error;
2027
af5bc92d
TT		 2028 memcpy((char *) entries2, (char *) (entries + icount1),
2029 icount2 * sizeof(struct dx_entry));
2030 dx_set_count(entries, icount1);
2031 dx_set_count(entries2, icount2);
2032 dx_set_limit(entries2, dx_node_limit(dir));
ac27a0ec
DK		 2033
2034 /* Which index block gets the new entry? */
2035 if (at - entries >= icount1) {
2036 frame->at = at = at - entries - icount1 + entries2;
2037 frame->entries = entries = entries2;
2038 swap(frame->bh, bh2);
2039 }
af5bc92d
TT		 2040 dx_insert_block(frames + 0, hash2, newblock);
2041 dxtrace(dx_show_index("node", frames[1].entries));
2042 dxtrace(dx_show_index("node",
ac27a0ec 2043 ((struct dx_node *) bh2->b_data)->entries));
dbe89444 2044 err = ext4_handle_dirty_dx_node(handle, dir, bh2);
ac27a0ec
DK		 2045 if (err)
2046 goto journal_error;
2047 brelse (bh2);
2048 } else {
4776004f
TT		 2049 dxtrace(printk(KERN_DEBUG
2050 "Creating second level index...\n"));
ac27a0ec
DK		 2051 memcpy((char *) entries2, (char *) entries,
2052 icount * sizeof(struct dx_entry));
2053 dx_set_limit(entries2, dx_node_limit(dir));
2054
2055 /* Set up root */
2056 dx_set_count(entries, 1);
2057 dx_set_block(entries + 0, newblock);
2058 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
2059
2060 /* Add new access path frame */
2061 frame = frames + 1;
2062 frame->at = at = at - entries + entries2;
2063 frame->entries = entries = entries2;
2064 frame->bh = bh2;
617ba13b 2065 err = ext4_journal_get_write_access(handle,
ac27a0ec
DK		 2066 frame->bh);
2067 if (err)
2068 goto journal_error;
2069 }
dbe89444 2070 err = ext4_handle_dirty_dx_node(handle, dir, frames[0].bh);
b4097142
TT		 2071 if (err) {
2072 ext4_std_error(inode->i_sb, err);
2073 goto cleanup;
2074 }
ac27a0ec
DK		 2075 }
2076 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
2077 if (!de)
2078 goto cleanup;
2079 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
ac27a0ec
DK		 2080 goto cleanup;
2081
2082journal_error:
617ba13b 2083 ext4_std_error(dir->i_sb, err);
ac27a0ec
DK		 2084cleanup:
2085 if (bh)
2086 brelse(bh);
2087 dx_release(frames);
2088 return err;
2089}
ac27a0ec
DK		 2090
2091/*
617ba13b 2092 * ext4_delete_entry deletes a directory entry by merging it with the
ac27a0ec
DK		 2093 * previous entry
2094 */
af5bc92d
TT		 2095static int ext4_delete_entry(handle_t *handle,
2096 struct inode *dir,
2097 struct ext4_dir_entry_2 *de_del,
2098 struct buffer_head *bh)
ac27a0ec 2099{
af5bc92d 2100 struct ext4_dir_entry_2 *de, *pde;
3d0518f4 2101 unsigned int blocksize = dir->i_sb->s_blocksize;
b0336e8d 2102 int csum_size = 0;
b4097142 2103 int i, err;
ac27a0ec 2104
b0336e8d
DW		 2105 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2106 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2107 csum_size = sizeof(struct ext4_dir_entry_tail);
2108
ac27a0ec
DK		 2109 i = 0;
2110 pde = NULL;
617ba13b 2111 de = (struct ext4_dir_entry_2 *) bh->b_data;
b0336e8d 2112 while (i < bh->b_size - csum_size) {
226ba972
TM		 2113 if (ext4_check_dir_entry(dir, NULL, de, bh,
2114 bh->b_data, bh->b_size, i))
ac27a0ec
DK		 2115 return -EIO;
2116 if (de == de_del) {
2117 BUFFER_TRACE(bh, "get_write_access");
b4097142
TT		 2118 err = ext4_journal_get_write_access(handle, bh);
2119 if (unlikely(err)) {
2120 ext4_std_error(dir->i_sb, err);
2121 return err;
2122 }
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++;
0390131b 2133 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
b0336e8d 2134 err = ext4_handle_dirty_dirent_node(handle, dir, bh);
b4097142
TT		 2135 if (unlikely(err)) {
2136 ext4_std_error(dir->i_sb, err);
2137 return err;
2138 }
ac27a0ec
DK		 2139 return 0;
2140 }
3d0518f4 2141 i += ext4_rec_len_from_disk(de->rec_len, blocksize);
ac27a0ec 2142 pde = de;
3d0518f4 2143 de = ext4_next_entry(de, blocksize);
ac27a0ec
DK		 2144 }
2145 return -ENOENT;
2146}
2147
f8628a14
AD		 2148/*
2149 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2,
2150 * since this indicates that nlinks count was previously 1.
2151 */
2152static void ext4_inc_count(handle_t *handle, struct inode *inode)
2153{
2154 inc_nlink(inode);
2155 if (is_dx(inode) && inode->i_nlink > 1) {
2156 /* limit is 16-bit i_links_count */
2157 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) {
bfe86848 2158 set_nlink(inode, 1);
f8628a14
AD		 2159 EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb,
2160 EXT4_FEATURE_RO_COMPAT_DIR_NLINK);
2161 }
2162 }
2163}
2164
2165/*
2166 * If a directory had nlink == 1, then we should let it be 1. This indicates
2167 * directory has >EXT4_LINK_MAX subdirs.
2168 */
2169static void ext4_dec_count(handle_t *handle, struct inode *inode)
2170{
909a4cf1
AD		 2171 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
2172 drop_nlink(inode);
f8628a14
AD		 2173}
2174
2175
617ba13b 2176static int ext4_add_nondir(handle_t *handle,
ac27a0ec
DK		 2177 struct dentry *dentry, struct inode *inode)
2178{
617ba13b 2179 int err = ext4_add_entry(handle, dentry, inode);
ac27a0ec 2180 if (!err) {
617ba13b 2181 ext4_mark_inode_dirty(handle, inode);
6b38e842 2182 unlock_new_inode(inode);
8fc37ec5 2183 d_instantiate(dentry, inode);
ac27a0ec
DK		 2184 return 0;
2185 }
731b9a54 2186 drop_nlink(inode);
6b38e842 2187 unlock_new_inode(inode);
ac27a0ec
DK		 2188 iput(inode);
2189 return err;
2190}
2191
2192/*
2193 * By the time this is called, we already have created
2194 * the directory cache entry for the new file, but it
2195 * is so far negative - it has no inode.
2196 *
2197 * If the create succeeds, we fill in the inode information
2198 * with d_instantiate().
2199 */
4acdaf27 2200static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
ebfc3b49 2201 bool excl)
ac27a0ec
DK		 2202{
2203 handle_t *handle;
af5bc92d 2204 struct inode *inode;
ac27a0ec
DK		 2205 int err, retries = 0;
2206
871a2931 2207 dquot_initialize(dir);
907f4554 2208
ac27a0ec 2209retry:
617ba13b
MC		 2210 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2211 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
5aca07eb 2212 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
ac27a0ec
DK		 2213 if (IS_ERR(handle))
2214 return PTR_ERR(handle);
2215
2216 if (IS_DIRSYNC(dir))
0390131b 2217 ext4_handle_sync(handle);
ac27a0ec 2218
5cb81dab 2219 inode = ext4_new_inode(handle, dir, mode, &dentry->d_name, 0, NULL);
ac27a0ec
DK		 2220 err = PTR_ERR(inode);
2221 if (!IS_ERR(inode)) {
617ba13b
MC		 2222 inode->i_op = &ext4_file_inode_operations;
2223 inode->i_fop = &ext4_file_operations;
2224 ext4_set_aops(inode);
2225 err = ext4_add_nondir(handle, dentry, inode);
ac27a0ec 2226 }
617ba13b
MC		 2227 ext4_journal_stop(handle);
2228 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2229 goto retry;
2230 return err;
2231}
2232
af5bc92d 2233static int ext4_mknod(struct inode *dir, struct dentry *dentry,
1a67aafb 2234 umode_t mode, dev_t rdev)
ac27a0ec
DK		 2235{
2236 handle_t *handle;
2237 struct inode *inode;
2238 int err, retries = 0;
2239
2240 if (!new_valid_dev(rdev))
2241 return -EINVAL;
2242
871a2931 2243 dquot_initialize(dir);
907f4554 2244
ac27a0ec 2245retry:
617ba13b
MC		 2246 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2247 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
5aca07eb 2248 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
ac27a0ec
DK		 2249 if (IS_ERR(handle))
2250 return PTR_ERR(handle);
2251
2252 if (IS_DIRSYNC(dir))
0390131b 2253 ext4_handle_sync(handle);
ac27a0ec 2254
5cb81dab 2255 inode = ext4_new_inode(handle, dir, mode, &dentry->d_name, 0, NULL);
ac27a0ec
DK		 2256 err = PTR_ERR(inode);
2257 if (!IS_ERR(inode)) {
2258 init_special_inode(inode, inode->i_mode, rdev);
617ba13b 2259 inode->i_op = &ext4_special_inode_operations;
617ba13b 2260 err = ext4_add_nondir(handle, dentry, inode);
ac27a0ec 2261 }
617ba13b
MC		 2262 ext4_journal_stop(handle);
2263 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2264 goto retry;
2265 return err;
2266}
2267
a774f9c2
TM		 2268struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
2269 struct ext4_dir_entry_2 *de,
2270 int blocksize, int csum_size,
2271 unsigned int parent_ino, int dotdot_real_len)
2272{
2273 de->inode = cpu_to_le32(inode->i_ino);
2274 de->name_len = 1;
2275 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
2276 blocksize);
2277 strcpy(de->name, ".");
2278 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2279
2280 de = ext4_next_entry(de, blocksize);
2281 de->inode = cpu_to_le32(parent_ino);
2282 de->name_len = 2;
2283 if (!dotdot_real_len)
2284 de->rec_len = ext4_rec_len_to_disk(blocksize -
2285 (csum_size + EXT4_DIR_REC_LEN(1)),
2286 blocksize);
2287 else
2288 de->rec_len = ext4_rec_len_to_disk(
2289 EXT4_DIR_REC_LEN(de->name_len), blocksize);
2290 strcpy(de->name, "..");
2291 ext4_set_de_type(inode->i_sb, de, S_IFDIR);
2292
2293 return ext4_next_entry(de, blocksize);
2294}
2295
2296static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
2297 struct inode *inode)
ac27a0ec 2298{
dabd991f 2299 struct buffer_head *dir_block = NULL;
af5bc92d 2300 struct ext4_dir_entry_2 *de;
b0336e8d 2301 struct ext4_dir_entry_tail *t;
3d0518f4 2302 unsigned int blocksize = dir->i_sb->s_blocksize;
b0336e8d 2303 int csum_size = 0;
a774f9c2 2304 int err;
ac27a0ec 2305
b0336e8d
DW		 2306 if (EXT4_HAS_RO_COMPAT_FEATURE(dir->i_sb,
2307 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
2308 csum_size = sizeof(struct ext4_dir_entry_tail);
2309
3c47d541
TM		 2310 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
2311 err = ext4_try_create_inline_dir(handle, dir, inode);
2312 if (err < 0 && err != -ENOSPC)
2313 goto out;
2314 if (!err)
2315 goto out;
2316 }
2317
a774f9c2
TM		 2318 inode->i_size = EXT4_I(inode)->i_disksize = blocksize;
2319 dir_block = ext4_bread(handle, inode, 0, 1, &err);
2320 if (!(dir_block = ext4_bread(handle, inode, 0, 1, &err))) {
2321 if (!err) {
2322 err = -EIO;
2323 ext4_error(inode->i_sb,
2324 "Directory hole detected on inode %lu\n",
2325 inode->i_ino);
2326 }
2327 goto out;
2328 }
2329 BUFFER_TRACE(dir_block, "get_write_access");
2330 err = ext4_journal_get_write_access(handle, dir_block);
2331 if (err)
2332 goto out;
2333 de = (struct ext4_dir_entry_2 *)dir_block->b_data;
2334 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
2335 set_nlink(inode, 2);
2336 if (csum_size) {
2337 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
2338 initialize_dirent_tail(t, blocksize);
2339 }
2340
2341 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
2342 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
2343 if (err)
2344 goto out;
2345 set_buffer_verified(dir_block);
2346out:
2347 brelse(dir_block);
2348 return err;
2349}
2350
2351static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
2352{
2353 handle_t *handle;
2354 struct inode *inode;
2355 int err, retries = 0;
2356
f8628a14 2357 if (EXT4_DIR_LINK_MAX(dir))
ac27a0ec
DK		 2358 return -EMLINK;
2359
871a2931 2360 dquot_initialize(dir);
907f4554 2361
ac27a0ec 2362retry:
617ba13b
MC		 2363 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2364 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
5aca07eb 2365 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb));
ac27a0ec
DK		 2366 if (IS_ERR(handle))
2367 return PTR_ERR(handle);
2368
2369 if (IS_DIRSYNC(dir))
0390131b 2370 ext4_handle_sync(handle);
ac27a0ec 2371
11013911 2372 inode = ext4_new_inode(handle, dir, S_IFDIR | mode,
5cb81dab 2373 &dentry->d_name, 0, NULL);
ac27a0ec
DK		 2374 err = PTR_ERR(inode);
2375 if (IS_ERR(inode))
2376 goto out_stop;
2377
617ba13b
MC		 2378 inode->i_op = &ext4_dir_inode_operations;
2379 inode->i_fop = &ext4_dir_operations;
a774f9c2 2380 err = ext4_init_new_dir(handle, dir, inode);
dabd991f
NK		 2381 if (err)
2382 goto out_clear_inode;
2383 err = ext4_mark_inode_dirty(handle, inode);
2384 if (!err)
2385 err = ext4_add_entry(handle, dentry, inode);
ac27a0ec 2386 if (err) {
4cdeed86
AK		 2387out_clear_inode:
2388 clear_nlink(inode);
6b38e842 2389 unlock_new_inode(inode);
617ba13b 2390 ext4_mark_inode_dirty(handle, inode);
af5bc92d 2391 iput(inode);
ac27a0ec
DK		 2392 goto out_stop;
2393 }
f8628a14 2394 ext4_inc_count(handle, dir);
617ba13b 2395 ext4_update_dx_flag(dir);
dabd991f
NK		 2396 err = ext4_mark_inode_dirty(handle, dir);
2397 if (err)
2398 goto out_clear_inode;
6b38e842 2399 unlock_new_inode(inode);
8fc37ec5 2400 d_instantiate(dentry, inode);
ac27a0ec 2401out_stop:
617ba13b
MC		 2402 ext4_journal_stop(handle);
2403 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2404 goto retry;
2405 return err;
2406}
2407
2408/*
2409 * routine to check that the specified directory is empty (for rmdir)
2410 */
af5bc92d 2411static int empty_dir(struct inode *inode)
ac27a0ec 2412{
498e5f24 2413 unsigned int offset;
af5bc92d
TT		 2414 struct buffer_head *bh;
2415 struct ext4_dir_entry_2 *de, *de1;
2416 struct super_block *sb;
ac27a0ec
DK		 2417 int err = 0;
2418
2419 sb = inode->i_sb;
617ba13b 2420 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2) ||
af5bc92d 2421 !(bh = ext4_bread(NULL, inode, 0, 0, &err))) {
ac27a0ec 2422 if (err)
24676da4
TT		 2423 EXT4_ERROR_INODE(inode,
2424 "error %d reading directory lblock 0", err);
ac27a0ec 2425 else
12062ddd 2426 ext4_warning(inode->i_sb,
ac27a0ec
DK		 2427 "bad directory (dir #%lu) - no data block",
2428 inode->i_ino);
2429 return 1;
2430 }
b0336e8d
DW		 2431 if (!buffer_verified(bh) &&
2432 !ext4_dirent_csum_verify(inode,
2433 (struct ext4_dir_entry *)bh->b_data)) {
2434 EXT4_ERROR_INODE(inode, "checksum error reading directory "
2435 "lblock 0");
2436 return -EIO;
2437 }
2438 set_buffer_verified(bh);
617ba13b 2439 de = (struct ext4_dir_entry_2 *) bh->b_data;
3d0518f4 2440 de1 = ext4_next_entry(de, sb->s_blocksize);
ac27a0ec
DK		 2441 if (le32_to_cpu(de->inode) != inode->i_ino ||
2442 !le32_to_cpu(de1->inode) ||
af5bc92d
TT		 2443 strcmp(".", de->name) ||
2444 strcmp("..", de1->name)) {
12062ddd 2445 ext4_warning(inode->i_sb,
af5bc92d
TT		 2446 "bad directory (dir #%lu) - no `.' or `..'",
2447 inode->i_ino);
2448 brelse(bh);
ac27a0ec
DK		 2449 return 1;
2450 }
3d0518f4
WY		 2451 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
2452 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
2453 de = ext4_next_entry(de1, sb->s_blocksize);
af5bc92d 2454 while (offset < inode->i_size) {
ac27a0ec 2455 if (!bh ||
24676da4
TT		 2456 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
2457 unsigned int lblock;
ac27a0ec 2458 err = 0;
af5bc92d 2459 brelse(bh);
24676da4
TT		 2460 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
2461 bh = ext4_bread(NULL, inode, lblock, 0, &err);
ac27a0ec
DK		 2462 if (!bh) {
2463 if (err)
24676da4
TT		 2464 EXT4_ERROR_INODE(inode,
2465 "error %d reading directory "
2466 "lblock %u", err, lblock);
6d1ab10e
CM		 2467 else
2468 ext4_warning(inode->i_sb,
2469 "bad directory (dir #%lu) - no data block",
2470 inode->i_ino);
2471
ac27a0ec
DK		 2472 offset += sb->s_blocksize;
2473 continue;
2474 }
b0336e8d
DW		 2475 if (!buffer_verified(bh) &&
2476 !ext4_dirent_csum_verify(inode,
2477 (struct ext4_dir_entry *)bh->b_data)) {
2478 EXT4_ERROR_INODE(inode, "checksum error "
2479 "reading directory lblock 0");
2480 return -EIO;
2481 }
2482 set_buffer_verified(bh);
617ba13b 2483 de = (struct ext4_dir_entry_2 *) bh->b_data;
ac27a0ec 2484 }
226ba972
TM		 2485 if (ext4_check_dir_entry(inode, NULL, de, bh,
2486 bh->b_data, bh->b_size, offset)) {
617ba13b 2487 de = (struct ext4_dir_entry_2 *)(bh->b_data +
ac27a0ec
DK		 2488 sb->s_blocksize);
2489 offset = (offset | (sb->s_blocksize - 1)) + 1;
2490 continue;
2491 }
2492 if (le32_to_cpu(de->inode)) {
af5bc92d 2493 brelse(bh);
ac27a0ec
DK		 2494 return 0;
2495 }
3d0518f4
WY		 2496 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
2497 de = ext4_next_entry(de, sb->s_blocksize);
ac27a0ec 2498 }
af5bc92d 2499 brelse(bh);
ac27a0ec
DK		 2500 return 1;
2501}
2502
617ba13b 2503/* ext4_orphan_add() links an unlinked or truncated inode into a list of
ac27a0ec
DK		 2504 * such inodes, starting at the superblock, in case we crash before the
2505 * file is closed/deleted, or in case the inode truncate spans multiple
2506 * transactions and the last transaction is not recovered after a crash.
2507 *
2508 * At filesystem recovery time, we walk this list deleting unlinked
617ba13b 2509 * inodes and truncating linked inodes in ext4_orphan_cleanup().
ac27a0ec 2510 */
617ba13b 2511int ext4_orphan_add(handle_t *handle, struct inode *inode)
ac27a0ec
DK		 2512{
2513 struct super_block *sb = inode->i_sb;
617ba13b 2514 struct ext4_iloc iloc;
ac27a0ec
DK		 2515 int err = 0, rc;
2516
c9b92530 2517 if (!EXT4_SB(sb)->s_journal)
0390131b
FM		 2518 return 0;
2519
3b9d4ed2 2520 mutex_lock(&EXT4_SB(sb)->s_orphan_lock);
617ba13b 2521 if (!list_empty(&EXT4_I(inode)->i_orphan))
ac27a0ec
DK		 2522 goto out_unlock;
2523
afb86178
LC		 2524 /*
2525 * Orphan handling is only valid for files with data blocks
2526 * being truncated, or files being unlinked. Note that we either
2527 * hold i_mutex, or the inode can not be referenced from outside,
2528 * so i_nlink should not be bumped due to race
ac27a0ec 2529 */
af5bc92d
TT		 2530 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
2531 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
ac27a0ec 2532
617ba13b
MC		 2533 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
2534 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
ac27a0ec
DK		 2535 if (err)
2536 goto out_unlock;
2537
617ba13b 2538 err = ext4_reserve_inode_write(handle, inode, &iloc);
ac27a0ec
DK		 2539 if (err)
2540 goto out_unlock;
6e3617e5
DM		 2541 /*
2542 * Due to previous errors inode may be already a part of on-disk
2543 * orphan list. If so skip on-disk list modification.
2544 */
2545 if (NEXT_ORPHAN(inode) && NEXT_ORPHAN(inode) <=
2546 (le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)))
2547 goto mem_insert;
ac27a0ec
DK		 2548
2549 /* Insert this inode at the head of the on-disk orphan list... */
617ba13b
MC		 2550 NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan);
2551 EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
b50924c2 2552 err = ext4_handle_dirty_super(handle, sb);
617ba13b 2553 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
ac27a0ec
DK		 2554 if (!err)
2555 err = rc;
2556
2557 /* Only add to the head of the in-memory list if all the
2558 * previous operations succeeded. If the orphan_add is going to
2559 * fail (possibly taking the journal offline), we can't risk
2560 * leaving the inode on the orphan list: stray orphan-list
2561 * entries can cause panics at unmount time.
2562 *
2563 * This is safe: on error we're going to ignore the orphan list
2564 * anyway on the next recovery. */
6e3617e5 2565mem_insert:
ac27a0ec 2566 if (!err)
617ba13b 2567 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
ac27a0ec
DK		 2568
2569 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
2570 jbd_debug(4, "orphan inode %lu will point to %d\n",
2571 inode->i_ino, NEXT_ORPHAN(inode));
2572out_unlock:
3b9d4ed2 2573 mutex_unlock(&EXT4_SB(sb)->s_orphan_lock);
617ba13b 2574 ext4_std_error(inode->i_sb, err);
ac27a0ec
DK		 2575 return err;
2576}
2577
2578/*
617ba13b 2579 * ext4_orphan_del() removes an unlinked or truncated inode from the list
ac27a0ec
DK		 2580 * of such inodes stored on disk, because it is finally being cleaned up.
2581 */
617ba13b 2582int ext4_orphan_del(handle_t *handle, struct inode *inode)
ac27a0ec
DK		 2583{
2584 struct list_head *prev;
617ba13b
MC		 2585 struct ext4_inode_info *ei = EXT4_I(inode);
2586 struct ext4_sb_info *sbi;
498e5f24 2587 __u32 ino_next;
617ba13b 2588 struct ext4_iloc iloc;
ac27a0ec
DK		 2589 int err = 0;
2590
c9b92530 2591 if (!EXT4_SB(inode->i_sb)->s_journal)
0390131b
FM		 2592 return 0;
2593
3b9d4ed2
TT		 2594 mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
2595 if (list_empty(&ei->i_orphan))
2596 goto out;
ac27a0ec
DK		 2597
2598 ino_next = NEXT_ORPHAN(inode);
2599 prev = ei->i_orphan.prev;
617ba13b 2600 sbi = EXT4_SB(inode->i_sb);
ac27a0ec
DK		 2601
2602 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
2603
2604 list_del_init(&ei->i_orphan);
2605
2606 /* If we're on an error path, we may not have a valid
2607 * transaction handle with which to update the orphan list on
2608 * disk, but we still need to remove the inode from the linked
2609 * list in memory. */
c9b92530 2610 if (!handle)
ac27a0ec
DK		 2611 goto out;
2612
617ba13b 2613 err = ext4_reserve_inode_write(handle, inode, &iloc);
ac27a0ec
DK		 2614 if (err)
2615 goto out_err;
2616
2617 if (prev == &sbi->s_orphan) {
498e5f24 2618 jbd_debug(4, "superblock will point to %u\n", ino_next);
ac27a0ec 2619 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
617ba13b 2620 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
ac27a0ec
DK		 2621 if (err)
2622 goto out_brelse;
2623 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
b50924c2 2624 err = ext4_handle_dirty_super(handle, inode->i_sb);
ac27a0ec 2625 } else {
617ba13b 2626 struct ext4_iloc iloc2;
ac27a0ec 2627 struct inode *i_prev =
617ba13b 2628 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
ac27a0ec 2629
498e5f24 2630 jbd_debug(4, "orphan inode %lu will point to %u\n",
ac27a0ec 2631 i_prev->i_ino, ino_next);
617ba13b 2632 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
ac27a0ec
DK		 2633 if (err)
2634 goto out_brelse;
2635 NEXT_ORPHAN(i_prev) = ino_next;
617ba13b 2636 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
ac27a0ec
DK		 2637 }
2638 if (err)
2639 goto out_brelse;
2640 NEXT_ORPHAN(inode) = 0;
617ba13b 2641 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
ac27a0ec
DK		 2642
2643out_err:
617ba13b 2644 ext4_std_error(inode->i_sb, err);
ac27a0ec 2645out:
3b9d4ed2 2646 mutex_unlock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
ac27a0ec
DK		 2647 return err;
2648
2649out_brelse:
2650 brelse(iloc.bh);
2651 goto out_err;
2652}
2653
af5bc92d 2654static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
ac27a0ec
DK		 2655{
2656 int retval;
af5bc92d
TT		 2657 struct inode *inode;
2658 struct buffer_head *bh;
2659 struct ext4_dir_entry_2 *de;
ac27a0ec
DK		 2660 handle_t *handle;
2661
2662 /* Initialize quotas before so that eventual writes go in
2663 * separate transaction */
871a2931
CH		 2664 dquot_initialize(dir);
2665 dquot_initialize(dentry->d_inode);
907f4554 2666
617ba13b 2667 handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
ac27a0ec
DK		 2668 if (IS_ERR(handle))
2669 return PTR_ERR(handle);
2670
2671 retval = -ENOENT;
f702ba0f 2672 bh = ext4_find_entry(dir, &dentry->d_name, &de);
ac27a0ec
DK		 2673 if (!bh)
2674 goto end_rmdir;
2675
2676 if (IS_DIRSYNC(dir))
0390131b 2677 ext4_handle_sync(handle);
ac27a0ec
DK		 2678
2679 inode = dentry->d_inode;
2680
2681 retval = -EIO;
2682 if (le32_to_cpu(de->inode) != inode->i_ino)
2683 goto end_rmdir;
2684
2685 retval = -ENOTEMPTY;
af5bc92d 2686 if (!empty_dir(inode))
ac27a0ec
DK		 2687 goto end_rmdir;
2688
617ba13b 2689 retval = ext4_delete_entry(handle, dir, de, bh);
ac27a0ec
DK		 2690 if (retval)
2691 goto end_rmdir;
f8628a14 2692 if (!EXT4_DIR_LINK_EMPTY(inode))
12062ddd 2693 ext4_warning(inode->i_sb,
af5bc92d
TT		 2694 "empty directory has too many links (%d)",
2695 inode->i_nlink);
ac27a0ec
DK		 2696 inode->i_version++;
2697 clear_nlink(inode);
2698 /* There's no need to set i_disksize: the fact that i_nlink is
2699 * zero will ensure that the right thing happens during any
2700 * recovery. */
2701 inode->i_size = 0;
617ba13b 2702 ext4_orphan_add(handle, inode);
ef7f3835 2703 inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode);
617ba13b 2704 ext4_mark_inode_dirty(handle, inode);
f8628a14 2705 ext4_dec_count(handle, dir);
617ba13b
MC		 2706 ext4_update_dx_flag(dir);
2707 ext4_mark_inode_dirty(handle, dir);
ac27a0ec
DK		 2708
2709end_rmdir:
617ba13b 2710 ext4_journal_stop(handle);
af5bc92d 2711 brelse(bh);
ac27a0ec
DK		 2712 return retval;
2713}
2714
af5bc92d 2715static int ext4_unlink(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;
ac27a0ec
DK		 2721 handle_t *handle;
2722
0562e0ba 2723 trace_ext4_unlink_enter(dir, dentry);
ac27a0ec
DK		 2724 /* Initialize quotas before so that eventual writes go
2725 * in separate transaction */
871a2931
CH		 2726 dquot_initialize(dir);
2727 dquot_initialize(dentry->d_inode);
907f4554 2728
617ba13b 2729 handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
ac27a0ec
DK		 2730 if (IS_ERR(handle))
2731 return PTR_ERR(handle);
2732
2733 if (IS_DIRSYNC(dir))
0390131b 2734 ext4_handle_sync(handle);
ac27a0ec
DK		 2735
2736 retval = -ENOENT;
f702ba0f 2737 bh = ext4_find_entry(dir, &dentry->d_name, &de);
ac27a0ec
DK		 2738 if (!bh)
2739 goto end_unlink;
2740
2741 inode = dentry->d_inode;
2742
2743 retval = -EIO;
2744 if (le32_to_cpu(de->inode) != inode->i_ino)
2745 goto end_unlink;
2746
2747 if (!inode->i_nlink) {
12062ddd 2748 ext4_warning(inode->i_sb,
af5bc92d
TT		 2749 "Deleting nonexistent file (%lu), %d",
2750 inode->i_ino, inode->i_nlink);
bfe86848 2751 set_nlink(inode, 1);
ac27a0ec 2752 }
617ba13b 2753 retval = ext4_delete_entry(handle, dir, de, bh);
ac27a0ec
DK		 2754 if (retval)
2755 goto end_unlink;
ef7f3835 2756 dir->i_ctime = dir->i_mtime = ext4_current_time(dir);
617ba13b
MC		 2757 ext4_update_dx_flag(dir);
2758 ext4_mark_inode_dirty(handle, dir);
825f1481 2759 drop_nlink(inode);
ac27a0ec 2760 if (!inode->i_nlink)
617ba13b 2761 ext4_orphan_add(handle, inode);
ef7f3835 2762 inode->i_ctime = ext4_current_time(inode);
617ba13b 2763 ext4_mark_inode_dirty(handle, inode);
ac27a0ec
DK		 2764 retval = 0;
2765
2766end_unlink:
617ba13b 2767 ext4_journal_stop(handle);
af5bc92d 2768 brelse(bh);
0562e0ba 2769 trace_ext4_unlink_exit(dentry, retval);
ac27a0ec
DK		 2770 return retval;
2771}
2772
af5bc92d
TT		 2773static int ext4_symlink(struct inode *dir,
2774 struct dentry *dentry, const char *symname)
ac27a0ec
DK		 2775{
2776 handle_t *handle;
af5bc92d 2777 struct inode *inode;
ac27a0ec 2778 int l, err, retries = 0;
df5e6223 2779 int credits;
ac27a0ec
DK		 2780
2781 l = strlen(symname)+1;
2782 if (l > dir->i_sb->s_blocksize)
2783 return -ENAMETOOLONG;
2784
871a2931 2785 dquot_initialize(dir);
907f4554 2786
df5e6223
JK		 2787 if (l > EXT4_N_BLOCKS * 4) {
2788 /*
2789 * For non-fast symlinks, we just allocate inode and put it on
2790 * orphan list in the first transaction => we need bitmap,
8c208719
ES		 2791 * group descriptor, sb, inode block, quota blocks, and
2792 * possibly selinux xattr blocks.
df5e6223 2793 */
8c208719
ES		 2794 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
2795 EXT4_XATTR_TRANS_BLOCKS;
df5e6223
JK		 2796 } else {
2797 /*
2798 * Fast symlink. We have to add entry to directory
2799 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS),
2800 * allocate new inode (bitmap, group descriptor, inode block,
2801 * quota blocks, sb is already counted in previous macros).
2802 */
2803 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2804 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2805 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb);
2806 }
ac27a0ec 2807retry:
df5e6223 2808 handle = ext4_journal_start(dir, credits);
ac27a0ec
DK		 2809 if (IS_ERR(handle))
2810 return PTR_ERR(handle);
2811
2812 if (IS_DIRSYNC(dir))
0390131b 2813 ext4_handle_sync(handle);
ac27a0ec 2814
11013911 2815 inode = ext4_new_inode(handle, dir, S_IFLNK|S_IRWXUGO,
5cb81dab 2816 &dentry->d_name, 0, NULL);
ac27a0ec
DK		 2817 err = PTR_ERR(inode);
2818 if (IS_ERR(inode))
2819 goto out_stop;
2820
df5e6223 2821 if (l > EXT4_N_BLOCKS * 4) {
617ba13b
MC		 2822 inode->i_op = &ext4_symlink_inode_operations;
2823 ext4_set_aops(inode);
ac27a0ec 2824 /*
df5e6223
JK		 2825 * We cannot call page_symlink() with transaction started
2826 * because it calls into ext4_write_begin() which can wait
2827 * for transaction commit if we are running out of space
2828 * and thus we deadlock. So we have to stop transaction now
2829 * and restart it when symlink contents is written.
2830 *
2831 * To keep fs consistent in case of crash, we have to put inode
2832 * to orphan list in the mean time.
ac27a0ec 2833 */
df5e6223
JK		 2834 drop_nlink(inode);
2835 err = ext4_orphan_add(handle, inode);
2836 ext4_journal_stop(handle);
2837 if (err)
2838 goto err_drop_inode;
54566b2c 2839 err = __page_symlink(inode, symname, l, 1);
df5e6223
JK		 2840 if (err)
2841 goto err_drop_inode;
2842 /*
2843 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS
2844 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified
2845 */
2846 handle = ext4_journal_start(dir,
2847 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2848 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1);
2849 if (IS_ERR(handle)) {
2850 err = PTR_ERR(handle);
2851 goto err_drop_inode;
2852 }
0ce8c010 2853 set_nlink(inode, 1);
df5e6223 2854 err = ext4_orphan_del(handle, inode);
ac27a0ec 2855 if (err) {
df5e6223 2856 ext4_journal_stop(handle);
825f1481 2857 clear_nlink(inode);
df5e6223 2858 goto err_drop_inode;
ac27a0ec
DK		 2859 }
2860 } else {
e65187e6 2861 /* clear the extent format for fast symlink */
12e9b892 2862 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
617ba13b 2863 inode->i_op = &ext4_fast_symlink_inode_operations;
af5bc92d 2864 memcpy((char *)&EXT4_I(inode)->i_data, symname, l);
ac27a0ec
DK		 2865 inode->i_size = l-1;
2866 }
617ba13b
MC		 2867 EXT4_I(inode)->i_disksize = inode->i_size;
2868 err = ext4_add_nondir(handle, dentry, inode);
ac27a0ec 2869out_stop:
617ba13b
MC		 2870 ext4_journal_stop(handle);
2871 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2872 goto retry;
2873 return err;
df5e6223
JK		 2874err_drop_inode:
2875 unlock_new_inode(inode);
2876 iput(inode);
2877 return err;
ac27a0ec
DK		 2878}
2879
af5bc92d
TT		 2880static int ext4_link(struct dentry *old_dentry,
2881 struct inode *dir, struct dentry *dentry)
ac27a0ec
DK		 2882{
2883 handle_t *handle;
2884 struct inode *inode = old_dentry->d_inode;
2885 int err, retries = 0;
2886
b05ab1dc 2887 if (inode->i_nlink >= EXT4_LINK_MAX)
ac27a0ec 2888 return -EMLINK;
f8628a14 2889
871a2931 2890 dquot_initialize(dir);
907f4554 2891
ac27a0ec 2892retry:
617ba13b
MC		 2893 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2894 EXT4_INDEX_EXTRA_TRANS_BLOCKS);
ac27a0ec
DK		 2895 if (IS_ERR(handle))
2896 return PTR_ERR(handle);
2897
2898 if (IS_DIRSYNC(dir))
0390131b 2899 ext4_handle_sync(handle);
ac27a0ec 2900
ef7f3835 2901 inode->i_ctime = ext4_current_time(inode);
f8628a14 2902 ext4_inc_count(handle, inode);
7de9c6ee 2903 ihold(inode);
ac27a0ec 2904
6b38e842
AV		 2905 err = ext4_add_entry(handle, dentry, inode);
2906 if (!err) {
2907 ext4_mark_inode_dirty(handle, inode);
2908 d_instantiate(dentry, inode);
2909 } else {
2910 drop_nlink(inode);
2911 iput(inode);
2912 }
617ba13b
MC		 2913 ext4_journal_stop(handle);
2914 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
ac27a0ec
DK		 2915 goto retry;
2916 return err;
2917}
2918
3d0518f4
WY		 2919#define PARENT_INO(buffer, size) \
2920 (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer), size)->inode)
ac27a0ec
DK		 2921
2922/*
2923 * Anybody can rename anything with this: the permission checks are left to the
2924 * higher-level routines.
2925 */
af5bc92d
TT		 2926static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
2927 struct inode *new_dir, struct dentry *new_dentry)
ac27a0ec
DK		 2928{
2929 handle_t *handle;
af5bc92d
TT		 2930 struct inode *old_inode, *new_inode;
2931 struct buffer_head *old_bh, *new_bh, *dir_bh;
2932 struct ext4_dir_entry_2 *old_de, *new_de;
8750c6d5 2933 int retval, force_da_alloc = 0;
ac27a0ec 2934
871a2931
CH		 2935 dquot_initialize(old_dir);
2936 dquot_initialize(new_dir);
907f4554 2937
ac27a0ec
DK		 2938 old_bh = new_bh = dir_bh = NULL;
2939
2940 /* Initialize quotas before so that eventual writes go
2941 * in separate transaction */
2942 if (new_dentry->d_inode)
871a2931 2943 dquot_initialize(new_dentry->d_inode);
617ba13b
MC		 2944 handle = ext4_journal_start(old_dir, 2 *
2945 EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) +
2946 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
ac27a0ec
DK		 2947 if (IS_ERR(handle))
2948 return PTR_ERR(handle);
2949
2950 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
0390131b 2951 ext4_handle_sync(handle);
ac27a0ec 2952
f702ba0f 2953 old_bh = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de);
ac27a0ec
DK		 2954 /*
2955 * Check for inode number is _not_ due to possible IO errors.
2956 * We might rmdir the source, keep it as pwd of some process
2957 * and merrily kill the link to whatever was created under the
2958 * same name. Goodbye sticky bit ;-<
2959 */
2960 old_inode = old_dentry->d_inode;
2961 retval = -ENOENT;
2962 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
2963 goto end_rename;
2964
2965 new_inode = new_dentry->d_inode;
f702ba0f 2966 new_bh = ext4_find_entry(new_dir, &new_dentry->d_name, &new_de);
ac27a0ec
DK		 2967 if (new_bh) {
2968 if (!new_inode) {
af5bc92d 2969 brelse(new_bh);
ac27a0ec
DK		 2970 new_bh = NULL;
2971 }
2972 }
2973 if (S_ISDIR(old_inode->i_mode)) {
2974 if (new_inode) {
2975 retval = -ENOTEMPTY;
af5bc92d 2976 if (!empty_dir(new_inode))
ac27a0ec
DK		 2977 goto end_rename;
2978 }
2979 retval = -EIO;
6d1ab10e
CM		 2980 if (!(dir_bh = ext4_bread(handle, old_inode, 0, 0, &retval))) {
2981 if (!retval) {
2982 retval = -EIO;
2983 ext4_error(old_inode->i_sb,
2984 "Directory hole detected on inode %lu\n",
2985 old_inode->i_ino);
2986 }
ac27a0ec 2987 goto end_rename;
6d1ab10e 2988 }
b0336e8d
DW		 2989 if (!buffer_verified(dir_bh) &&
2990 !ext4_dirent_csum_verify(old_inode,
2991 (struct ext4_dir_entry *)dir_bh->b_data))
2992 goto end_rename;
2993 set_buffer_verified(dir_bh);
3d0518f4
WY		 2994 if (le32_to_cpu(PARENT_INO(dir_bh->b_data,
2995 old_dir->i_sb->s_blocksize)) != old_dir->i_ino)
ac27a0ec
DK		 2996 goto end_rename;
2997 retval = -EMLINK;
af5bc92d 2998 if (!new_inode && new_dir != old_dir &&
2c94eb86 2999 EXT4_DIR_LINK_MAX(new_dir))
ac27a0ec 3000 goto end_rename;
ef607893
AG		 3001 BUFFER_TRACE(dir_bh, "get_write_access");
3002 retval = ext4_journal_get_write_access(handle, dir_bh);
3003 if (retval)
3004 goto end_rename;
ac27a0ec
DK		 3005 }
3006 if (!new_bh) {
af5bc92d 3007 retval = ext4_add_entry(handle, new_dentry, old_inode);
ac27a0ec
DK		 3008 if (retval)
3009 goto end_rename;
3010 } else {
3011 BUFFER_TRACE(new_bh, "get write access");
ef607893
AG		 3012 retval = ext4_journal_get_write_access(handle, new_bh);
3013 if (retval)
3014 goto end_rename;
ac27a0ec 3015 new_de->inode = cpu_to_le32(old_inode->i_ino);
617ba13b
MC		 3016 if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
3017 EXT4_FEATURE_INCOMPAT_FILETYPE))
ac27a0ec
DK		 3018 new_de->file_type = old_de->file_type;
3019 new_dir->i_version++;
53b7e9f6
JK		 3020 new_dir->i_ctime = new_dir->i_mtime =
3021 ext4_current_time(new_dir);
3022 ext4_mark_inode_dirty(handle, new_dir);
0390131b 3023 BUFFER_TRACE(new_bh, "call ext4_handle_dirty_metadata");
b0336e8d 3024 retval = ext4_handle_dirty_dirent_node(handle, new_dir, new_bh);
b4097142
TT		 3025 if (unlikely(retval)) {
3026 ext4_std_error(new_dir->i_sb, retval);
3027 goto end_rename;
3028 }
ac27a0ec
DK		 3029 brelse(new_bh);
3030 new_bh = NULL;
3031 }
3032
3033 /*
3034 * Like most other Unix systems, set the ctime for inodes on a
3035 * rename.
3036 */
ef7f3835 3037 old_inode->i_ctime = ext4_current_time(old_inode);
617ba13b 3038 ext4_mark_inode_dirty(handle, old_inode);
ac27a0ec
DK		 3039
3040 /*
3041 * ok, that's it
3042 */
3043 if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
3044 old_de->name_len != old_dentry->d_name.len ||
3045 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
617ba13b 3046 (retval = ext4_delete_entry(handle, old_dir,
ac27a0ec
DK		 3047 old_de, old_bh)) == -ENOENT) {
3048 /* old_de could have moved from under us during htree split, so
3049 * make sure that we are deleting the right entry. We might
3050 * also be pointing to a stale entry in the unused part of
3051 * old_bh so just checking inum and the name isn't enough. */
3052 struct buffer_head *old_bh2;
617ba13b 3053 struct ext4_dir_entry_2 *old_de2;
ac27a0ec 3054
f702ba0f 3055 old_bh2 = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de2);
ac27a0ec 3056 if (old_bh2) {
617ba13b 3057 retval = ext4_delete_entry(handle, old_dir,
ac27a0ec
DK		 3058 old_de2, old_bh2);
3059 brelse(old_bh2);
3060 }
3061 }
3062 if (retval) {
12062ddd 3063 ext4_warning(old_dir->i_sb,
ac27a0ec
DK		 3064 "Deleting old file (%lu), %d, error=%d",
3065 old_dir->i_ino, old_dir->i_nlink, retval);
3066 }
3067
3068 if (new_inode) {
f8628a14 3069 ext4_dec_count(handle, new_inode);
ef7f3835 3070 new_inode->i_ctime = ext4_current_time(new_inode);
ac27a0ec 3071 }
ef7f3835 3072 old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir);
617ba13b 3073 ext4_update_dx_flag(old_dir);
ac27a0ec 3074 if (dir_bh) {
3d0518f4
WY		 3075 PARENT_INO(dir_bh->b_data, new_dir->i_sb->s_blocksize) =
3076 cpu_to_le32(new_dir->i_ino);
0390131b 3077 BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata");
ef58f69c
TM		 3078 if (is_dx(old_inode)) {
3079 retval = ext4_handle_dirty_dx_node(handle,
3080 old_inode,
3081 dir_bh);
3082 } else {
3083 retval = ext4_handle_dirty_dirent_node(handle,
3084 old_inode,
3085 dir_bh);
3086 }
b4097142
TT		 3087 if (retval) {
3088 ext4_std_error(old_dir->i_sb, retval);
3089 goto end_rename;
3090 }
f8628a14 3091 ext4_dec_count(handle, old_dir);
ac27a0ec 3092 if (new_inode) {
f8628a14 3093 /* checked empty_dir above, can't have another parent,
825f1481 3094 * ext4_dec_count() won't work for many-linked dirs */
6d6b77f1 3095 clear_nlink(new_inode);
ac27a0ec 3096 } else {
f8628a14 3097 ext4_inc_count(handle, new_dir);
617ba13b
MC		 3098 ext4_update_dx_flag(new_dir);
3099 ext4_mark_inode_dirty(handle, new_dir);
ac27a0ec
DK		 3100 }
3101 }
617ba13b 3102 ext4_mark_inode_dirty(handle, old_dir);
ac27a0ec 3103 if (new_inode) {
617ba13b 3104 ext4_mark_inode_dirty(handle, new_inode);
ac27a0ec 3105 if (!new_inode->i_nlink)
617ba13b 3106 ext4_orphan_add(handle, new_inode);
afd4672d
TT		 3107 if (!test_opt(new_dir->i_sb, NO_AUTO_DA_ALLOC))
3108 force_da_alloc = 1;
ac27a0ec
DK		 3109 }
3110 retval = 0;
3111
3112end_rename:
af5bc92d
TT		 3113 brelse(dir_bh);
3114 brelse(old_bh);
3115 brelse(new_bh);
617ba13b 3116 ext4_journal_stop(handle);
8750c6d5
TT		 3117 if (retval == 0 && force_da_alloc)
3118 ext4_alloc_da_blocks(old_inode);
ac27a0ec
DK		 3119 return retval;
3120}
3121
3122/*
3123 * directories can handle most operations...
3124 */
754661f1 3125const struct inode_operations ext4_dir_inode_operations = {
617ba13b
MC		 3126 .create = ext4_create,
3127 .lookup = ext4_lookup,
3128 .link = ext4_link,
3129 .unlink = ext4_unlink,
3130 .symlink = ext4_symlink,
3131 .mkdir = ext4_mkdir,
3132 .rmdir = ext4_rmdir,
3133 .mknod = ext4_mknod,
3134 .rename = ext4_rename,
3135 .setattr = ext4_setattr,
03010a33 3136#ifdef CONFIG_EXT4_FS_XATTR
ac27a0ec
DK		 3137 .setxattr = generic_setxattr,
3138 .getxattr = generic_getxattr,
617ba13b 3139 .listxattr = ext4_listxattr,
ac27a0ec
DK		 3140 .removexattr = generic_removexattr,
3141#endif
4e34e719 3142 .get_acl = ext4_get_acl,
abc8746e 3143 .fiemap = ext4_fiemap,
ac27a0ec
DK		 3144};
3145
754661f1 3146const struct inode_operations ext4_special_inode_operations = {
617ba13b 3147 .setattr = ext4_setattr,
03010a33 3148#ifdef CONFIG_EXT4_FS_XATTR
ac27a0ec
DK		 3149 .setxattr = generic_setxattr,
3150 .getxattr = generic_getxattr,
617ba13b 3151 .listxattr = ext4_listxattr,
ac27a0ec
DK		 3152 .removexattr = generic_removexattr,
3153#endif
4e34e719 3154 .get_acl = ext4_get_acl,
ac27a0ec 3155};
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