iget: stop EXT2 from using iget() and read_inode()
[deliverable/linux.git] / fs / ext3 / namei.c
CommitLineData
1da177e4
LT
1/*
2 * linux/fs/ext3/namei.c
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
e9ad5620 18 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
1da177e4 19 * Hash Tree Directory indexing (c)
e9ad5620 20 * Daniel Phillips, 2001
1da177e4 21 * Hash Tree Directory indexing porting
e9ad5620 22 * Christopher Li, 2002
1da177e4 23 * Hash Tree Directory indexing cleanup
e9ad5620 24 * Theodore Ts'o, 2002
1da177e4
LT
25 */
26
27#include <linux/fs.h>
28#include <linux/pagemap.h>
29#include <linux/jbd.h>
30#include <linux/time.h>
31#include <linux/ext3_fs.h>
32#include <linux/ext3_jbd.h>
33#include <linux/fcntl.h>
34#include <linux/stat.h>
35#include <linux/string.h>
36#include <linux/quotaops.h>
37#include <linux/buffer_head.h>
caa38fb0 38#include <linux/bio.h>
381be254
BD
39
40#include "namei.h"
1da177e4
LT
41#include "xattr.h"
42#include "acl.h"
43
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
49#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
50#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
51
52static struct buffer_head *ext3_append(handle_t *handle,
53 struct inode *inode,
54 u32 *block, int *err)
55{
56 struct buffer_head *bh;
57
58 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
59
60 if ((bh = ext3_bread(handle, inode, *block, 1, err))) {
61 inode->i_size += inode->i_sb->s_blocksize;
62 EXT3_I(inode)->i_disksize = inode->i_size;
63 ext3_journal_get_write_access(handle,bh);
64 }
65 return bh;
66}
67
68#ifndef assert
69#define assert(test) J_ASSERT(test)
70#endif
71
72#ifndef swap
73#define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0)
74#endif
75
76#ifdef DX_DEBUG
77#define dxtrace(command) command
78#else
ae6ddcc5 79#define dxtrace(command)
1da177e4
LT
80#endif
81
82struct fake_dirent
83{
84 __le32 inode;
85 __le16 rec_len;
86 u8 name_len;
87 u8 file_type;
88};
89
90struct dx_countlimit
91{
92 __le16 limit;
93 __le16 count;
94};
95
96struct dx_entry
97{
98 __le32 hash;
99 __le32 block;
100};
101
102/*
103 * dx_root_info is laid out so that if it should somehow get overlaid by a
104 * dirent the two low bits of the hash version will be zero. Therefore, the
105 * hash version mod 4 should never be 0. Sincerely, the paranoia department.
106 */
107
108struct dx_root
109{
110 struct fake_dirent dot;
111 char dot_name[4];
112 struct fake_dirent dotdot;
113 char dotdot_name[4];
114 struct dx_root_info
115 {
116 __le32 reserved_zero;
117 u8 hash_version;
118 u8 info_length; /* 8 */
119 u8 indirect_levels;
120 u8 unused_flags;
121 }
122 info;
123 struct dx_entry entries[0];
124};
125
126struct dx_node
127{
128 struct fake_dirent fake;
129 struct dx_entry entries[0];
130};
131
132
133struct dx_frame
134{
135 struct buffer_head *bh;
136 struct dx_entry *entries;
137 struct dx_entry *at;
138};
139
140struct dx_map_entry
141{
142 u32 hash;
ef2b02d3
ES
143 u16 offs;
144 u16 size;
1da177e4
LT
145};
146
1da177e4
LT
147static inline unsigned dx_get_block (struct dx_entry *entry);
148static void dx_set_block (struct dx_entry *entry, unsigned value);
149static inline unsigned dx_get_hash (struct dx_entry *entry);
150static void dx_set_hash (struct dx_entry *entry, unsigned value);
151static unsigned dx_get_count (struct dx_entry *entries);
152static unsigned dx_get_limit (struct dx_entry *entries);
153static void dx_set_count (struct dx_entry *entries, unsigned value);
154static void dx_set_limit (struct dx_entry *entries, unsigned value);
155static unsigned dx_root_limit (struct inode *dir, unsigned infosize);
156static unsigned dx_node_limit (struct inode *dir);
157static struct dx_frame *dx_probe(struct dentry *dentry,
158 struct inode *dir,
159 struct dx_hash_info *hinfo,
160 struct dx_frame *frame,
161 int *err);
162static void dx_release (struct dx_frame *frames);
163static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
164 struct dx_hash_info *hinfo, struct dx_map_entry map[]);
165static void dx_sort_map(struct dx_map_entry *map, unsigned count);
166static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to,
167 struct dx_map_entry *offsets, int count);
168static struct ext3_dir_entry_2* dx_pack_dirents (char *base, int size);
169static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block);
170static int ext3_htree_next_block(struct inode *dir, __u32 hash,
171 struct dx_frame *frame,
ae6ddcc5 172 struct dx_frame *frames,
1da177e4
LT
173 __u32 *start_hash);
174static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
175 struct ext3_dir_entry_2 **res_dir, int *err);
176static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
177 struct inode *inode);
178
7c06a8dc
JK
179/*
180 * p is at least 6 bytes before the end of page
181 */
182static inline struct ext3_dir_entry_2 *
183ext3_next_entry(struct ext3_dir_entry_2 *p)
184{
185 return (struct ext3_dir_entry_2 *)((char *)p +
186 ext3_rec_len_from_disk(p->rec_len));
187}
188
1da177e4
LT
189/*
190 * Future: use high four bits of block for coalesce-on-delete flags
191 * Mask them off for now.
192 */
193
194static inline unsigned dx_get_block (struct dx_entry *entry)
195{
196 return le32_to_cpu(entry->block) & 0x00ffffff;
197}
198
199static inline void dx_set_block (struct dx_entry *entry, unsigned value)
200{
201 entry->block = cpu_to_le32(value);
202}
203
204static inline unsigned dx_get_hash (struct dx_entry *entry)
205{
206 return le32_to_cpu(entry->hash);
207}
208
209static inline void dx_set_hash (struct dx_entry *entry, unsigned value)
210{
211 entry->hash = cpu_to_le32(value);
212}
213
214static inline unsigned dx_get_count (struct dx_entry *entries)
215{
216 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
217}
218
219static inline unsigned dx_get_limit (struct dx_entry *entries)
220{
221 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
222}
223
224static inline void dx_set_count (struct dx_entry *entries, unsigned value)
225{
226 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
227}
228
229static inline void dx_set_limit (struct dx_entry *entries, unsigned value)
230{
231 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
232}
233
234static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
235{
236 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) -
237 EXT3_DIR_REC_LEN(2) - infosize;
238 return 0? 20: entry_space / sizeof(struct dx_entry);
239}
240
241static inline unsigned dx_node_limit (struct inode *dir)
242{
243 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0);
244 return 0? 22: entry_space / sizeof(struct dx_entry);
245}
246
247/*
248 * Debug
249 */
250#ifdef DX_DEBUG
251static void dx_show_index (char * label, struct dx_entry *entries)
252{
253 int i, n = dx_get_count (entries);
254 printk("%s index ", label);
255 for (i = 0; i < n; i++)
256 {
257 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i));
258 }
259 printk("\n");
260}
261
262struct stats
ae6ddcc5 263{
1da177e4
LT
264 unsigned names;
265 unsigned space;
266 unsigned bcount;
267};
268
269static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de,
270 int size, int show_names)
271{
272 unsigned names = 0, space = 0;
273 char *base = (char *) de;
274 struct dx_hash_info h = *hinfo;
275
276 printk("names: ");
277 while ((char *) de < base + size)
278 {
279 if (de->inode)
280 {
281 if (show_names)
282 {
283 int len = de->name_len;
284 char *name = de->name;
285 while (len--) printk("%c", *name++);
286 ext3fs_dirhash(de->name, de->name_len, &h);
287 printk(":%x.%u ", h.hash,
288 ((char *) de - base));
289 }
290 space += EXT3_DIR_REC_LEN(de->name_len);
e9ad5620 291 names++;
1da177e4 292 }
7c06a8dc 293 de = ext3_next_entry(de);
1da177e4
LT
294 }
295 printk("(%i)\n", names);
296 return (struct stats) { names, space, 1 };
297}
298
299struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
300 struct dx_entry *entries, int levels)
301{
302 unsigned blocksize = dir->i_sb->s_blocksize;
303 unsigned count = dx_get_count (entries), names = 0, space = 0, i;
304 unsigned bcount = 0;
305 struct buffer_head *bh;
306 int err;
307 printk("%i indexed blocks...\n", count);
308 for (i = 0; i < count; i++, entries++)
309 {
310 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0;
311 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
312 struct stats stats;
313 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
314 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue;
315 stats = levels?
316 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
317 dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0);
318 names += stats.names;
319 space += stats.space;
320 bcount += stats.bcount;
321 brelse (bh);
322 }
323 if (bcount)
324 printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ",
325 names, space/bcount,(space/bcount)*100/blocksize);
326 return (struct stats) { names, space, bcount};
327}
328#endif /* DX_DEBUG */
329
330/*
331 * Probe for a directory leaf block to search.
332 *
333 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
334 * error in the directory index, and the caller should fall back to
335 * searching the directory normally. The callers of dx_probe **MUST**
336 * check for this error code, and make sure it never gets reflected
337 * back to userspace.
338 */
339static struct dx_frame *
340dx_probe(struct dentry *dentry, struct inode *dir,
341 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
342{
343 unsigned count, indirect;
344 struct dx_entry *at, *entries, *p, *q, *m;
345 struct dx_root *root;
346 struct buffer_head *bh;
347 struct dx_frame *frame = frame_in;
348 u32 hash;
349
350 frame->bh = NULL;
351 if (dentry)
352 dir = dentry->d_parent->d_inode;
353 if (!(bh = ext3_bread (NULL,dir, 0, 0, err)))
354 goto fail;
355 root = (struct dx_root *) bh->b_data;
356 if (root->info.hash_version != DX_HASH_TEA &&
357 root->info.hash_version != DX_HASH_HALF_MD4 &&
358 root->info.hash_version != DX_HASH_LEGACY) {
359 ext3_warning(dir->i_sb, __FUNCTION__,
360 "Unrecognised inode hash code %d",
361 root->info.hash_version);
362 brelse(bh);
363 *err = ERR_BAD_DX_DIR;
364 goto fail;
365 }
366 hinfo->hash_version = root->info.hash_version;
367 hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed;
368 if (dentry)
369 ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo);
370 hash = hinfo->hash;
371
372 if (root->info.unused_flags & 1) {
373 ext3_warning(dir->i_sb, __FUNCTION__,
374 "Unimplemented inode hash flags: %#06x",
375 root->info.unused_flags);
376 brelse(bh);
377 *err = ERR_BAD_DX_DIR;
378 goto fail;
379 }
380
381 if ((indirect = root->info.indirect_levels) > 1) {
382 ext3_warning(dir->i_sb, __FUNCTION__,
383 "Unimplemented inode hash depth: %#06x",
384 root->info.indirect_levels);
385 brelse(bh);
386 *err = ERR_BAD_DX_DIR;
387 goto fail;
388 }
389
390 entries = (struct dx_entry *) (((char *)&root->info) +
391 root->info.info_length);
3d82abae
ES
392
393 if (dx_get_limit(entries) != dx_root_limit(dir,
394 root->info.info_length)) {
395 ext3_warning(dir->i_sb, __FUNCTION__,
396 "dx entry: limit != root limit");
397 brelse(bh);
398 *err = ERR_BAD_DX_DIR;
399 goto fail;
400 }
401
1da177e4
LT
402 dxtrace (printk("Look up %x", hash));
403 while (1)
404 {
405 count = dx_get_count(entries);
3d82abae
ES
406 if (!count || count > dx_get_limit(entries)) {
407 ext3_warning(dir->i_sb, __FUNCTION__,
408 "dx entry: no count or count > limit");
409 brelse(bh);
410 *err = ERR_BAD_DX_DIR;
411 goto fail2;
412 }
413
1da177e4
LT
414 p = entries + 1;
415 q = entries + count - 1;
416 while (p <= q)
417 {
418 m = p + (q - p)/2;
419 dxtrace(printk("."));
420 if (dx_get_hash(m) > hash)
421 q = m - 1;
422 else
423 p = m + 1;
424 }
425
426 if (0) // linear search cross check
427 {
428 unsigned n = count - 1;
429 at = entries;
430 while (n--)
431 {
432 dxtrace(printk(","));
433 if (dx_get_hash(++at) > hash)
434 {
435 at--;
436 break;
437 }
438 }
439 assert (at == p - 1);
440 }
441
442 at = p - 1;
443 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
444 frame->bh = bh;
445 frame->entries = entries;
446 frame->at = at;
447 if (!indirect--) return frame;
448 if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err)))
449 goto fail2;
450 at = entries = ((struct dx_node *) bh->b_data)->entries;
3d82abae
ES
451 if (dx_get_limit(entries) != dx_node_limit (dir)) {
452 ext3_warning(dir->i_sb, __FUNCTION__,
453 "dx entry: limit != node limit");
454 brelse(bh);
455 *err = ERR_BAD_DX_DIR;
456 goto fail2;
457 }
1da177e4 458 frame++;
3d82abae 459 frame->bh = NULL;
1da177e4
LT
460 }
461fail2:
462 while (frame >= frame_in) {
463 brelse(frame->bh);
464 frame--;
465 }
466fail:
3d82abae
ES
467 if (*err == ERR_BAD_DX_DIR)
468 ext3_warning(dir->i_sb, __FUNCTION__,
469 "Corrupt dir inode %ld, running e2fsck is "
470 "recommended.", dir->i_ino);
1da177e4
LT
471 return NULL;
472}
473
474static void dx_release (struct dx_frame *frames)
475{
476 if (frames[0].bh == NULL)
477 return;
478
479 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
480 brelse(frames[1].bh);
481 brelse(frames[0].bh);
482}
483
484/*
485 * This function increments the frame pointer to search the next leaf
486 * block, and reads in the necessary intervening nodes if the search
487 * should be necessary. Whether or not the search is necessary is
488 * controlled by the hash parameter. If the hash value is even, then
489 * the search is only continued if the next block starts with that
490 * hash value. This is used if we are searching for a specific file.
491 *
492 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
493 *
494 * This function returns 1 if the caller should continue to search,
495 * or 0 if it should not. If there is an error reading one of the
496 * index blocks, it will a negative error code.
497 *
498 * If start_hash is non-null, it will be filled in with the starting
499 * hash of the next page.
500 */
501static int ext3_htree_next_block(struct inode *dir, __u32 hash,
502 struct dx_frame *frame,
ae6ddcc5 503 struct dx_frame *frames,
1da177e4
LT
504 __u32 *start_hash)
505{
506 struct dx_frame *p;
507 struct buffer_head *bh;
508 int err, num_frames = 0;
509 __u32 bhash;
510
511 p = frame;
512 /*
513 * Find the next leaf page by incrementing the frame pointer.
514 * If we run out of entries in the interior node, loop around and
515 * increment pointer in the parent node. When we break out of
516 * this loop, num_frames indicates the number of interior
517 * nodes need to be read.
518 */
519 while (1) {
520 if (++(p->at) < p->entries + dx_get_count(p->entries))
521 break;
522 if (p == frames)
523 return 0;
524 num_frames++;
525 p--;
526 }
527
528 /*
529 * If the hash is 1, then continue only if the next page has a
530 * continuation hash of any value. This is used for readdir
531 * handling. Otherwise, check to see if the hash matches the
532 * desired contiuation hash. If it doesn't, return since
533 * there's no point to read in the successive index pages.
534 */
535 bhash = dx_get_hash(p->at);
536 if (start_hash)
537 *start_hash = bhash;
538 if ((hash & 1) == 0) {
539 if ((bhash & ~1) != hash)
540 return 0;
541 }
542 /*
543 * If the hash is HASH_NB_ALWAYS, we always go to the next
544 * block so no check is necessary
545 */
546 while (num_frames--) {
547 if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at),
548 0, &err)))
549 return err; /* Failure */
550 p++;
551 brelse (p->bh);
552 p->bh = bh;
553 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
554 }
555 return 1;
556}
557
558
1da177e4
LT
559/*
560 * This function fills a red-black tree with information from a
561 * directory block. It returns the number directory entries loaded
562 * into the tree. If there is an error it is returned in err.
563 */
564static int htree_dirblock_to_tree(struct file *dir_file,
565 struct inode *dir, int block,
566 struct dx_hash_info *hinfo,
567 __u32 start_hash, __u32 start_minor_hash)
568{
569 struct buffer_head *bh;
570 struct ext3_dir_entry_2 *de, *top;
571 int err, count = 0;
572
573 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
574 if (!(bh = ext3_bread (NULL, dir, block, 0, &err)))
575 return err;
576
577 de = (struct ext3_dir_entry_2 *) bh->b_data;
578 top = (struct ext3_dir_entry_2 *) ((char *) de +
579 dir->i_sb->s_blocksize -
580 EXT3_DIR_REC_LEN(0));
581 for (; de < top; de = ext3_next_entry(de)) {
40b85134
ES
582 if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
583 (block<<EXT3_BLOCK_SIZE_BITS(dir->i_sb))
584 +((char *)de - bh->b_data))) {
585 /* On error, skip the f_pos to the next block. */
586 dir_file->f_pos = (dir_file->f_pos |
587 (dir->i_sb->s_blocksize - 1)) + 1;
588 brelse (bh);
589 return count;
590 }
1da177e4
LT
591 ext3fs_dirhash(de->name, de->name_len, hinfo);
592 if ((hinfo->hash < start_hash) ||
593 ((hinfo->hash == start_hash) &&
594 (hinfo->minor_hash < start_minor_hash)))
595 continue;
596 if (de->inode == 0)
597 continue;
598 if ((err = ext3_htree_store_dirent(dir_file,
599 hinfo->hash, hinfo->minor_hash, de)) != 0) {
600 brelse(bh);
601 return err;
602 }
603 count++;
604 }
605 brelse(bh);
606 return count;
607}
608
609
610/*
611 * This function fills a red-black tree with information from a
612 * directory. We start scanning the directory in hash order, starting
613 * at start_hash and start_minor_hash.
614 *
615 * This function returns the number of entries inserted into the tree,
616 * or a negative error code.
617 */
618int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
619 __u32 start_minor_hash, __u32 *next_hash)
620{
621 struct dx_hash_info hinfo;
622 struct ext3_dir_entry_2 *de;
623 struct dx_frame frames[2], *frame;
624 struct inode *dir;
625 int block, err;
626 int count = 0;
627 int ret;
628 __u32 hashval;
629
630 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
631 start_minor_hash));
fe21a693 632 dir = dir_file->f_path.dentry->d_inode;
1da177e4
LT
633 if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) {
634 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
635 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
636 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
637 start_hash, start_minor_hash);
638 *next_hash = ~0;
639 return count;
640 }
641 hinfo.hash = start_hash;
642 hinfo.minor_hash = 0;
fe21a693 643 frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err);
1da177e4
LT
644 if (!frame)
645 return err;
646
647 /* Add '.' and '..' from the htree header */
648 if (!start_hash && !start_minor_hash) {
649 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
650 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0)
651 goto errout;
652 count++;
653 }
654 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
655 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
656 de = ext3_next_entry(de);
657 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0)
658 goto errout;
659 count++;
660 }
661
662 while (1) {
663 block = dx_get_block(frame->at);
664 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
665 start_hash, start_minor_hash);
666 if (ret < 0) {
667 err = ret;
668 goto errout;
669 }
670 count += ret;
671 hashval = ~0;
ae6ddcc5 672 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS,
1da177e4
LT
673 frame, frames, &hashval);
674 *next_hash = hashval;
675 if (ret < 0) {
676 err = ret;
677 goto errout;
678 }
679 /*
680 * Stop if: (a) there are no more entries, or
681 * (b) we have inserted at least one entry and the
682 * next hash value is not a continuation
683 */
684 if ((ret == 0) ||
685 (count && ((hashval & 1) == 0)))
686 break;
687 }
688 dx_release(frames);
ae6ddcc5 689 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n",
1da177e4
LT
690 count, *next_hash));
691 return count;
692errout:
693 dx_release(frames);
694 return (err);
695}
696
697
698/*
699 * Directory block splitting, compacting
700 */
701
ef2b02d3
ES
702/*
703 * Create map of hash values, offsets, and sizes, stored at end of block.
704 * Returns number of entries mapped.
705 */
1da177e4
LT
706static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
707 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
708{
709 int count = 0;
710 char *base = (char *) de;
711 struct dx_hash_info h = *hinfo;
712
713 while ((char *) de < base + size)
714 {
715 if (de->name_len && de->inode) {
716 ext3fs_dirhash(de->name, de->name_len, &h);
717 map_tail--;
718 map_tail->hash = h.hash;
ef2b02d3
ES
719 map_tail->offs = (u16) ((char *) de - base);
720 map_tail->size = le16_to_cpu(de->rec_len);
1da177e4
LT
721 count++;
722 cond_resched();
723 }
724 /* XXX: do we need to check rec_len == 0 case? -Chris */
7c06a8dc 725 de = ext3_next_entry(de);
1da177e4
LT
726 }
727 return count;
728}
729
ef2b02d3 730/* Sort map by hash value */
1da177e4
LT
731static void dx_sort_map (struct dx_map_entry *map, unsigned count)
732{
733 struct dx_map_entry *p, *q, *top = map + count - 1;
734 int more;
735 /* Combsort until bubble sort doesn't suck */
736 while (count > 2)
737 {
738 count = count*10/13;
739 if (count - 9 < 2) /* 9, 10 -> 11 */
740 count = 11;
741 for (p = top, q = p - count; q >= map; p--, q--)
742 if (p->hash < q->hash)
743 swap(*p, *q);
744 }
745 /* Garden variety bubble sort */
746 do {
747 more = 0;
748 q = top;
749 while (q-- > map)
750 {
751 if (q[1].hash >= q[0].hash)
752 continue;
753 swap(*(q+1), *q);
754 more = 1;
755 }
756 } while(more);
757}
758
759static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
760{
761 struct dx_entry *entries = frame->entries;
762 struct dx_entry *old = frame->at, *new = old + 1;
763 int count = dx_get_count(entries);
764
765 assert(count < dx_get_limit(entries));
766 assert(old < entries + count);
767 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
768 dx_set_hash(new, hash);
769 dx_set_block(new, block);
770 dx_set_count(entries, count + 1);
771}
1da177e4
LT
772
773static void ext3_update_dx_flag(struct inode *inode)
774{
775 if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb,
776 EXT3_FEATURE_COMPAT_DIR_INDEX))
777 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL;
778}
779
780/*
781 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure.
782 *
783 * `len <= EXT3_NAME_LEN' is guaranteed by caller.
784 * `de != NULL' is guaranteed by caller.
785 */
786static inline int ext3_match (int len, const char * const name,
787 struct ext3_dir_entry_2 * de)
788{
789 if (len != de->name_len)
790 return 0;
791 if (!de->inode)
792 return 0;
793 return !memcmp(name, de->name, len);
794}
795
796/*
797 * Returns 0 if not found, -1 on failure, and 1 on success
798 */
799static inline int search_dirblock(struct buffer_head * bh,
800 struct inode *dir,
801 struct dentry *dentry,
802 unsigned long offset,
803 struct ext3_dir_entry_2 ** res_dir)
804{
805 struct ext3_dir_entry_2 * de;
806 char * dlimit;
807 int de_len;
808 const char *name = dentry->d_name.name;
809 int namelen = dentry->d_name.len;
810
811 de = (struct ext3_dir_entry_2 *) bh->b_data;
812 dlimit = bh->b_data + dir->i_sb->s_blocksize;
813 while ((char *) de < dlimit) {
814 /* this code is executed quadratically often */
815 /* do minimal checking `by hand' */
816
817 if ((char *) de + namelen <= dlimit &&
818 ext3_match (namelen, name, de)) {
819 /* found a match - just to be sure, do a full check */
820 if (!ext3_check_dir_entry("ext3_find_entry",
821 dir, de, bh, offset))
822 return -1;
823 *res_dir = de;
824 return 1;
825 }
826 /* prevent looping on a bad block */
7c06a8dc 827 de_len = ext3_rec_len_from_disk(de->rec_len);
1da177e4
LT
828 if (de_len <= 0)
829 return -1;
830 offset += de_len;
831 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len);
832 }
833 return 0;
834}
835
836
837/*
838 * ext3_find_entry()
839 *
840 * finds an entry in the specified directory with the wanted name. It
841 * returns the cache buffer in which the entry was found, and the entry
842 * itself (as a parameter - res_dir). It does NOT read the inode of the
843 * entry - you'll have to do that yourself if you want to.
844 *
845 * The returned buffer_head has ->b_count elevated. The caller is expected
846 * to brelse() it when appropriate.
847 */
848static struct buffer_head * ext3_find_entry (struct dentry *dentry,
849 struct ext3_dir_entry_2 ** res_dir)
850{
851 struct super_block * sb;
852 struct buffer_head * bh_use[NAMEI_RA_SIZE];
853 struct buffer_head * bh, *ret = NULL;
854 unsigned long start, block, b;
855 int ra_max = 0; /* Number of bh's in the readahead
856 buffer, bh_use[] */
857 int ra_ptr = 0; /* Current index into readahead
858 buffer */
859 int num = 0;
860 int nblocks, i, err;
861 struct inode *dir = dentry->d_parent->d_inode;
862 int namelen;
1da177e4
LT
863
864 *res_dir = NULL;
865 sb = dir->i_sb;
1da177e4 866 namelen = dentry->d_name.len;
1da177e4
LT
867 if (namelen > EXT3_NAME_LEN)
868 return NULL;
1da177e4
LT
869 if (is_dx(dir)) {
870 bh = ext3_dx_find_entry(dentry, res_dir, &err);
871 /*
872 * On success, or if the error was file not found,
873 * return. Otherwise, fall back to doing a search the
874 * old fashioned way.
875 */
876 if (bh || (err != ERR_BAD_DX_DIR))
877 return bh;
878 dxtrace(printk("ext3_find_entry: dx failed, falling back\n"));
879 }
1da177e4
LT
880 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
881 start = EXT3_I(dir)->i_dir_start_lookup;
882 if (start >= nblocks)
883 start = 0;
884 block = start;
885restart:
886 do {
887 /*
888 * We deal with the read-ahead logic here.
889 */
890 if (ra_ptr >= ra_max) {
891 /* Refill the readahead buffer */
892 ra_ptr = 0;
893 b = block;
894 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
895 /*
896 * Terminate if we reach the end of the
897 * directory and must wrap, or if our
898 * search has finished at this block.
899 */
900 if (b >= nblocks || (num && block == start)) {
901 bh_use[ra_max] = NULL;
902 break;
903 }
904 num++;
905 bh = ext3_getblk(NULL, dir, b++, 0, &err);
906 bh_use[ra_max] = bh;
907 if (bh)
caa38fb0 908 ll_rw_block(READ_META, 1, &bh);
1da177e4
LT
909 }
910 }
911 if ((bh = bh_use[ra_ptr++]) == NULL)
912 goto next;
913 wait_on_buffer(bh);
914 if (!buffer_uptodate(bh)) {
915 /* read error, skip block & hope for the best */
916 ext3_error(sb, __FUNCTION__, "reading directory #%lu "
917 "offset %lu", dir->i_ino, block);
918 brelse(bh);
919 goto next;
920 }
921 i = search_dirblock(bh, dir, dentry,
922 block << EXT3_BLOCK_SIZE_BITS(sb), res_dir);
923 if (i == 1) {
924 EXT3_I(dir)->i_dir_start_lookup = block;
925 ret = bh;
926 goto cleanup_and_exit;
927 } else {
928 brelse(bh);
929 if (i < 0)
930 goto cleanup_and_exit;
931 }
932 next:
933 if (++block >= nblocks)
934 block = 0;
935 } while (block != start);
936
937 /*
938 * If the directory has grown while we were searching, then
939 * search the last part of the directory before giving up.
940 */
941 block = nblocks;
942 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
943 if (block < nblocks) {
944 start = 0;
945 goto restart;
946 }
947
948cleanup_and_exit:
949 /* Clean up the read-ahead blocks */
950 for (; ra_ptr < ra_max; ra_ptr++)
951 brelse (bh_use[ra_ptr]);
952 return ret;
953}
954
1da177e4
LT
955static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
956 struct ext3_dir_entry_2 **res_dir, int *err)
957{
958 struct super_block * sb;
959 struct dx_hash_info hinfo;
960 u32 hash;
961 struct dx_frame frames[2], *frame;
962 struct ext3_dir_entry_2 *de, *top;
963 struct buffer_head *bh;
964 unsigned long block;
965 int retval;
966 int namelen = dentry->d_name.len;
967 const u8 *name = dentry->d_name.name;
968 struct inode *dir = dentry->d_parent->d_inode;
969
970 sb = dir->i_sb;
acfa1823
AD
971 /* NFS may look up ".." - look at dx_root directory block */
972 if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
973 if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
974 return NULL;
975 } else {
976 frame = frames;
977 frame->bh = NULL; /* for dx_release() */
978 frame->at = (struct dx_entry *)frames; /* hack for zero entry*/
979 dx_set_block(frame->at, 0); /* dx_root block is 0 */
980 }
1da177e4
LT
981 hash = hinfo.hash;
982 do {
983 block = dx_get_block(frame->at);
984 if (!(bh = ext3_bread (NULL,dir, block, 0, err)))
985 goto errout;
986 de = (struct ext3_dir_entry_2 *) bh->b_data;
987 top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize -
988 EXT3_DIR_REC_LEN(0));
989 for (; de < top; de = ext3_next_entry(de))
990 if (ext3_match (namelen, name, de)) {
991 if (!ext3_check_dir_entry("ext3_find_entry",
992 dir, de, bh,
993 (block<<EXT3_BLOCK_SIZE_BITS(sb))
994 +((char *)de - bh->b_data))) {
995 brelse (bh);
fedee54d 996 *err = ERR_BAD_DX_DIR;
1da177e4
LT
997 goto errout;
998 }
999 *res_dir = de;
1000 dx_release (frames);
1001 return bh;
1002 }
1003 brelse (bh);
1004 /* Check to see if we should continue to search */
1005 retval = ext3_htree_next_block(dir, hash, frame,
1006 frames, NULL);
1007 if (retval < 0) {
1008 ext3_warning(sb, __FUNCTION__,
1009 "error reading index page in directory #%lu",
1010 dir->i_ino);
1011 *err = retval;
1012 goto errout;
1013 }
1014 } while (retval == 1);
1015
1016 *err = -ENOENT;
1017errout:
1018 dxtrace(printk("%s not found\n", name));
1019 dx_release (frames);
1020 return NULL;
1021}
1da177e4
LT
1022
1023static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
1024{
1025 struct inode * inode;
1026 struct ext3_dir_entry_2 * de;
1027 struct buffer_head * bh;
1028
1029 if (dentry->d_name.len > EXT3_NAME_LEN)
1030 return ERR_PTR(-ENAMETOOLONG);
1031
1032 bh = ext3_find_entry(dentry, &de);
1033 inode = NULL;
1034 if (bh) {
1035 unsigned long ino = le32_to_cpu(de->inode);
1036 brelse (bh);
2ccb48eb
NB
1037 if (!ext3_valid_inum(dir->i_sb, ino)) {
1038 ext3_error(dir->i_sb, "ext3_lookup",
1039 "bad inode number: %lu", ino);
1040 inode = NULL;
1041 } else
1042 inode = iget(dir->i_sb, ino);
1da177e4
LT
1043
1044 if (!inode)
1045 return ERR_PTR(-EACCES);
a6c15c2b
VA
1046
1047 if (is_bad_inode(inode)) {
1048 iput(inode);
1049 return ERR_PTR(-ENOENT);
1050 }
1da177e4 1051 }
ba7fe369 1052 return d_splice_alias(inode, dentry);
1da177e4
LT
1053}
1054
1055
1056struct dentry *ext3_get_parent(struct dentry *child)
1057{
1058 unsigned long ino;
1059 struct dentry *parent;
1060 struct inode *inode;
1061 struct dentry dotdot;
1062 struct ext3_dir_entry_2 * de;
1063 struct buffer_head *bh;
1064
1065 dotdot.d_name.name = "..";
1066 dotdot.d_name.len = 2;
1067 dotdot.d_parent = child; /* confusing, isn't it! */
1068
1069 bh = ext3_find_entry(&dotdot, &de);
1070 inode = NULL;
1071 if (!bh)
1072 return ERR_PTR(-ENOENT);
1073 ino = le32_to_cpu(de->inode);
1074 brelse(bh);
2ccb48eb
NB
1075
1076 if (!ext3_valid_inum(child->d_inode->i_sb, ino)) {
1077 ext3_error(child->d_inode->i_sb, "ext3_get_parent",
1078 "bad inode number: %lu", ino);
1079 inode = NULL;
1080 } else
1081 inode = iget(child->d_inode->i_sb, ino);
1da177e4
LT
1082
1083 if (!inode)
1084 return ERR_PTR(-EACCES);
1085
a6c15c2b
VA
1086 if (is_bad_inode(inode)) {
1087 iput(inode);
1088 return ERR_PTR(-ENOENT);
1089 }
1090
1da177e4
LT
1091 parent = d_alloc_anon(inode);
1092 if (!parent) {
1093 iput(inode);
1094 parent = ERR_PTR(-ENOMEM);
1095 }
1096 return parent;
ae6ddcc5 1097}
1da177e4
LT
1098
1099#define S_SHIFT 12
1100static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = {
1101 [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE,
1102 [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR,
1103 [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV,
1104 [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV,
1105 [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO,
1106 [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK,
1107 [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK,
1108};
1109
1110static inline void ext3_set_de_type(struct super_block *sb,
1111 struct ext3_dir_entry_2 *de,
1112 umode_t mode) {
1113 if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE))
1114 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
1115}
1116
ef2b02d3
ES
1117/*
1118 * Move count entries from end of map between two memory locations.
1119 * Returns pointer to last entry moved.
1120 */
1da177e4
LT
1121static struct ext3_dir_entry_2 *
1122dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
1123{
1124 unsigned rec_len = 0;
1125
1126 while (count--) {
1127 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs);
1128 rec_len = EXT3_DIR_REC_LEN(de->name_len);
1129 memcpy (to, de, rec_len);
1130 ((struct ext3_dir_entry_2 *) to)->rec_len =
7c06a8dc 1131 ext3_rec_len_to_disk(rec_len);
1da177e4
LT
1132 de->inode = 0;
1133 map++;
1134 to += rec_len;
1135 }
1136 return (struct ext3_dir_entry_2 *) (to - rec_len);
1137}
1138
ef2b02d3
ES
1139/*
1140 * Compact each dir entry in the range to the minimal rec_len.
1141 * Returns pointer to last entry in range.
1142 */
1da177e4
LT
1143static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size)
1144{
1145 struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base;
1146 unsigned rec_len = 0;
1147
1148 prev = to = de;
1149 while ((char*)de < base + size) {
7c06a8dc 1150 next = ext3_next_entry(de);
1da177e4
LT
1151 if (de->inode && de->name_len) {
1152 rec_len = EXT3_DIR_REC_LEN(de->name_len);
1153 if (de > to)
1154 memmove(to, de, rec_len);
7c06a8dc 1155 to->rec_len = ext3_rec_len_to_disk(rec_len);
1da177e4
LT
1156 prev = to;
1157 to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len);
1158 }
1159 de = next;
1160 }
1161 return prev;
1162}
1163
ef2b02d3
ES
1164/*
1165 * Split a full leaf block to make room for a new dir entry.
1166 * Allocate a new block, and move entries so that they are approx. equally full.
1167 * Returns pointer to de in block into which the new entry will be inserted.
1168 */
1da177e4
LT
1169static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1170 struct buffer_head **bh,struct dx_frame *frame,
1171 struct dx_hash_info *hinfo, int *error)
1172{
1173 unsigned blocksize = dir->i_sb->s_blocksize;
1174 unsigned count, continued;
1175 struct buffer_head *bh2;
1176 u32 newblock;
1177 u32 hash2;
1178 struct dx_map_entry *map;
1179 char *data1 = (*bh)->b_data, *data2;
ef2b02d3 1180 unsigned split, move, size, i;
1da177e4 1181 struct ext3_dir_entry_2 *de = NULL, *de2;
fedee54d 1182 int err = 0;
1da177e4 1183
fedee54d 1184 bh2 = ext3_append (handle, dir, &newblock, &err);
1da177e4
LT
1185 if (!(bh2)) {
1186 brelse(*bh);
1187 *bh = NULL;
1188 goto errout;
1189 }
1190
1191 BUFFER_TRACE(*bh, "get_write_access");
1192 err = ext3_journal_get_write_access(handle, *bh);
fedee54d
DM
1193 if (err)
1194 goto journal_error;
1195
1da177e4
LT
1196 BUFFER_TRACE(frame->bh, "get_write_access");
1197 err = ext3_journal_get_write_access(handle, frame->bh);
1198 if (err)
1199 goto journal_error;
1200
1201 data2 = bh2->b_data;
1202
1203 /* create map in the end of data2 block */
1204 map = (struct dx_map_entry *) (data2 + blocksize);
1205 count = dx_make_map ((struct ext3_dir_entry_2 *) data1,
1206 blocksize, hinfo, map);
1207 map -= count;
1da177e4 1208 dx_sort_map (map, count);
ef2b02d3
ES
1209 /* Split the existing block in the middle, size-wise */
1210 size = 0;
1211 move = 0;
1212 for (i = count-1; i >= 0; i--) {
1213 /* is more than half of this entry in 2nd half of the block? */
1214 if (size + map[i].size/2 > blocksize/2)
1215 break;
1216 size += map[i].size;
1217 move++;
1218 }
1219 /* map index at which we will split */
1220 split = count - move;
1da177e4
LT
1221 hash2 = map[split].hash;
1222 continued = hash2 == map[split - 1].hash;
1223 dxtrace(printk("Split block %i at %x, %i/%i\n",
1224 dx_get_block(frame->at), hash2, split, count-split));
1225
1226 /* Fancy dance to stay within two buffers */
1227 de2 = dx_move_dirents(data1, data2, map + split, count - split);
1228 de = dx_pack_dirents(data1,blocksize);
7c06a8dc
JK
1229 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
1230 de2->rec_len = ext3_rec_len_to_disk(data2 + blocksize - (char *) de2);
1da177e4
LT
1231 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1));
1232 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1));
1233
1234 /* Which block gets the new entry? */
1235 if (hinfo->hash >= hash2)
1236 {
1237 swap(*bh, bh2);
1238 de = de2;
1239 }
1240 dx_insert_block (frame, hash2 + continued, newblock);
1241 err = ext3_journal_dirty_metadata (handle, bh2);
1242 if (err)
1243 goto journal_error;
1244 err = ext3_journal_dirty_metadata (handle, frame->bh);
1245 if (err)
1246 goto journal_error;
1247 brelse (bh2);
1248 dxtrace(dx_show_index ("frame", frame->entries));
1da177e4 1249 return de;
fedee54d
DM
1250
1251journal_error:
1252 brelse(*bh);
1253 brelse(bh2);
1254 *bh = NULL;
1255 ext3_std_error(dir->i_sb, err);
1256errout:
1257 *error = err;
1258 return NULL;
1da177e4 1259}
1da177e4
LT
1260
1261
1262/*
1263 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1264 * it points to a directory entry which is guaranteed to be large
1265 * enough for new directory entry. If de is NULL, then
1266 * add_dirent_to_buf will attempt search the directory block for
1267 * space. It will return -ENOSPC if no space is available, and -EIO
1268 * and -EEXIST if directory entry already exists.
ae6ddcc5 1269 *
1da177e4
LT
1270 * NOTE! bh is NOT released in the case where ENOSPC is returned. In
1271 * all other cases bh is released.
1272 */
1273static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
1274 struct inode *inode, struct ext3_dir_entry_2 *de,
1275 struct buffer_head * bh)
1276{
1277 struct inode *dir = dentry->d_parent->d_inode;
1278 const char *name = dentry->d_name.name;
1279 int namelen = dentry->d_name.len;
1280 unsigned long offset = 0;
1281 unsigned short reclen;
1282 int nlen, rlen, err;
1283 char *top;
1284
1285 reclen = EXT3_DIR_REC_LEN(namelen);
1286 if (!de) {
1287 de = (struct ext3_dir_entry_2 *)bh->b_data;
1288 top = bh->b_data + dir->i_sb->s_blocksize - reclen;
1289 while ((char *) de <= top) {
1290 if (!ext3_check_dir_entry("ext3_add_entry", dir, de,
1291 bh, offset)) {
1292 brelse (bh);
1293 return -EIO;
1294 }
1295 if (ext3_match (namelen, name, de)) {
1296 brelse (bh);
1297 return -EEXIST;
1298 }
1299 nlen = EXT3_DIR_REC_LEN(de->name_len);
7c06a8dc 1300 rlen = ext3_rec_len_from_disk(de->rec_len);
1da177e4
LT
1301 if ((de->inode? rlen - nlen: rlen) >= reclen)
1302 break;
1303 de = (struct ext3_dir_entry_2 *)((char *)de + rlen);
1304 offset += rlen;
1305 }
1306 if ((char *) de > top)
1307 return -ENOSPC;
1308 }
1309 BUFFER_TRACE(bh, "get_write_access");
1310 err = ext3_journal_get_write_access(handle, bh);
1311 if (err) {
1312 ext3_std_error(dir->i_sb, err);
1313 brelse(bh);
1314 return err;
1315 }
1316
1317 /* By now the buffer is marked for journaling */
1318 nlen = EXT3_DIR_REC_LEN(de->name_len);
7c06a8dc 1319 rlen = ext3_rec_len_from_disk(de->rec_len);
1da177e4
LT
1320 if (de->inode) {
1321 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen);
7c06a8dc
JK
1322 de1->rec_len = ext3_rec_len_to_disk(rlen - nlen);
1323 de->rec_len = ext3_rec_len_to_disk(nlen);
1da177e4
LT
1324 de = de1;
1325 }
1326 de->file_type = EXT3_FT_UNKNOWN;
1327 if (inode) {
1328 de->inode = cpu_to_le32(inode->i_ino);
1329 ext3_set_de_type(dir->i_sb, de, inode->i_mode);
1330 } else
1331 de->inode = 0;
1332 de->name_len = namelen;
1333 memcpy (de->name, name, namelen);
1334 /*
1335 * XXX shouldn't update any times until successful
1336 * completion of syscall, but too many callers depend
1337 * on this.
1338 *
1339 * XXX similarly, too many callers depend on
1340 * ext3_new_inode() setting the times, but error
1341 * recovery deletes the inode, so the worst that can
1342 * happen is that the times are slightly out of date
1343 * and/or different from the directory change time.
1344 */
1345 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
1346 ext3_update_dx_flag(dir);
1347 dir->i_version++;
1348 ext3_mark_inode_dirty(handle, dir);
1349 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1350 err = ext3_journal_dirty_metadata(handle, bh);
1351 if (err)
1352 ext3_std_error(dir->i_sb, err);
1353 brelse(bh);
1354 return 0;
1355}
1356
1da177e4
LT
1357/*
1358 * This converts a one block unindexed directory to a 3 block indexed
1359 * directory, and adds the dentry to the indexed directory.
1360 */
1361static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1362 struct inode *inode, struct buffer_head *bh)
1363{
1364 struct inode *dir = dentry->d_parent->d_inode;
1365 const char *name = dentry->d_name.name;
1366 int namelen = dentry->d_name.len;
1367 struct buffer_head *bh2;
1368 struct dx_root *root;
1369 struct dx_frame frames[2], *frame;
1370 struct dx_entry *entries;
1371 struct ext3_dir_entry_2 *de, *de2;
1372 char *data1, *top;
1373 unsigned len;
1374 int retval;
1375 unsigned blocksize;
1376 struct dx_hash_info hinfo;
1377 u32 block;
1378 struct fake_dirent *fde;
1379
1380 blocksize = dir->i_sb->s_blocksize;
1381 dxtrace(printk("Creating index\n"));
1382 retval = ext3_journal_get_write_access(handle, bh);
1383 if (retval) {
1384 ext3_std_error(dir->i_sb, retval);
1385 brelse(bh);
1386 return retval;
1387 }
1388 root = (struct dx_root *) bh->b_data;
1389
1390 bh2 = ext3_append (handle, dir, &block, &retval);
1391 if (!(bh2)) {
1392 brelse(bh);
1393 return retval;
1394 }
1395 EXT3_I(dir)->i_flags |= EXT3_INDEX_FL;
1396 data1 = bh2->b_data;
1397
1398 /* The 0th block becomes the root, move the dirents out */
1399 fde = &root->dotdot;
7c06a8dc
JK
1400 de = (struct ext3_dir_entry_2 *)((char *)fde +
1401 ext3_rec_len_from_disk(fde->rec_len));
1da177e4
LT
1402 len = ((char *) root) + blocksize - (char *) de;
1403 memcpy (data1, de, len);
1404 de = (struct ext3_dir_entry_2 *) data1;
1405 top = data1 + len;
7c06a8dc 1406 while ((char *)(de2 = ext3_next_entry(de)) < top)
1da177e4 1407 de = de2;
7c06a8dc 1408 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de);
1da177e4
LT
1409 /* Initialize the root; the dot dirents already exist */
1410 de = (struct ext3_dir_entry_2 *) (&root->dotdot);
7c06a8dc 1411 de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2));
1da177e4
LT
1412 memset (&root->info, 0, sizeof(root->info));
1413 root->info.info_length = sizeof(root->info);
1414 root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
1415 entries = root->entries;
1416 dx_set_block (entries, 1);
1417 dx_set_count (entries, 1);
1418 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));
1419
1420 /* Initialize as for dx_probe */
1421 hinfo.hash_version = root->info.hash_version;
1422 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
1423 ext3fs_dirhash(name, namelen, &hinfo);
1424 frame = frames;
1425 frame->entries = entries;
1426 frame->at = entries;
1427 frame->bh = bh;
1428 bh = bh2;
1429 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
1430 dx_release (frames);
1431 if (!(de))
1432 return retval;
1433
1434 return add_dirent_to_buf(handle, dentry, inode, de, bh);
1435}
1da177e4
LT
1436
1437/*
1438 * ext3_add_entry()
1439 *
1440 * adds a file entry to the specified directory, using the same
1441 * semantics as ext3_find_entry(). It returns NULL if it failed.
1442 *
1443 * NOTE!! The inode part of 'de' is left at 0 - which means you
1444 * may not sleep between calling this and putting something into
1445 * the entry, as someone else might have used it while you slept.
1446 */
1447static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
1448 struct inode *inode)
1449{
1450 struct inode *dir = dentry->d_parent->d_inode;
1451 unsigned long offset;
1452 struct buffer_head * bh;
1453 struct ext3_dir_entry_2 *de;
1454 struct super_block * sb;
1455 int retval;
1da177e4 1456 int dx_fallback=0;
1da177e4 1457 unsigned blocksize;
1da177e4
LT
1458 u32 block, blocks;
1459
1460 sb = dir->i_sb;
1461 blocksize = sb->s_blocksize;
1462 if (!dentry->d_name.len)
1463 return -EINVAL;
1da177e4
LT
1464 if (is_dx(dir)) {
1465 retval = ext3_dx_add_entry(handle, dentry, inode);
1466 if (!retval || (retval != ERR_BAD_DX_DIR))
1467 return retval;
1468 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL;
1469 dx_fallback++;
1470 ext3_mark_inode_dirty(handle, dir);
1471 }
1da177e4
LT
1472 blocks = dir->i_size >> sb->s_blocksize_bits;
1473 for (block = 0, offset = 0; block < blocks; block++) {
1474 bh = ext3_bread(handle, dir, block, 0, &retval);
1475 if(!bh)
1476 return retval;
1477 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1478 if (retval != -ENOSPC)
1479 return retval;
1480
1da177e4
LT
1481 if (blocks == 1 && !dx_fallback &&
1482 EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
1483 return make_indexed_dir(handle, dentry, inode, bh);
1da177e4
LT
1484 brelse(bh);
1485 }
1486 bh = ext3_append(handle, dir, &block, &retval);
1487 if (!bh)
1488 return retval;
1489 de = (struct ext3_dir_entry_2 *) bh->b_data;
1490 de->inode = 0;
7c06a8dc 1491 de->rec_len = ext3_rec_len_to_disk(blocksize);
1da177e4
LT
1492 return add_dirent_to_buf(handle, dentry, inode, de, bh);
1493}
1494
1da177e4
LT
1495/*
1496 * Returns 0 for success, or a negative error value
1497 */
1498static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
1499 struct inode *inode)
1500{
1501 struct dx_frame frames[2], *frame;
1502 struct dx_entry *entries, *at;
1503 struct dx_hash_info hinfo;
1504 struct buffer_head * bh;
1505 struct inode *dir = dentry->d_parent->d_inode;
1506 struct super_block * sb = dir->i_sb;
1507 struct ext3_dir_entry_2 *de;
1508 int err;
1509
1510 frame = dx_probe(dentry, NULL, &hinfo, frames, &err);
1511 if (!frame)
1512 return err;
1513 entries = frame->entries;
1514 at = frame->at;
1515
1516 if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
1517 goto cleanup;
1518
1519 BUFFER_TRACE(bh, "get_write_access");
1520 err = ext3_journal_get_write_access(handle, bh);
1521 if (err)
1522 goto journal_error;
1523
1524 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1525 if (err != -ENOSPC) {
1526 bh = NULL;
1527 goto cleanup;
1528 }
1529
1530 /* Block full, should compress but for now just split */
1531 dxtrace(printk("using %u of %u node entries\n",
1532 dx_get_count(entries), dx_get_limit(entries)));
1533 /* Need to split index? */
1534 if (dx_get_count(entries) == dx_get_limit(entries)) {
1535 u32 newblock;
1536 unsigned icount = dx_get_count(entries);
1537 int levels = frame - frames;
1538 struct dx_entry *entries2;
1539 struct dx_node *node2;
1540 struct buffer_head *bh2;
1541
1542 if (levels && (dx_get_count(frames->entries) ==
1543 dx_get_limit(frames->entries))) {
1544 ext3_warning(sb, __FUNCTION__,
9f40668d 1545 "Directory index full!");
1da177e4
LT
1546 err = -ENOSPC;
1547 goto cleanup;
1548 }
1549 bh2 = ext3_append (handle, dir, &newblock, &err);
1550 if (!(bh2))
1551 goto cleanup;
1552 node2 = (struct dx_node *)(bh2->b_data);
1553 entries2 = node2->entries;
7c06a8dc 1554 node2->fake.rec_len = ext3_rec_len_to_disk(sb->s_blocksize);
1da177e4
LT
1555 node2->fake.inode = 0;
1556 BUFFER_TRACE(frame->bh, "get_write_access");
1557 err = ext3_journal_get_write_access(handle, frame->bh);
1558 if (err)
1559 goto journal_error;
1560 if (levels) {
1561 unsigned icount1 = icount/2, icount2 = icount - icount1;
1562 unsigned hash2 = dx_get_hash(entries + icount1);
1563 dxtrace(printk("Split index %i/%i\n", icount1, icount2));
1564
1565 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
1566 err = ext3_journal_get_write_access(handle,
1567 frames[0].bh);
1568 if (err)
1569 goto journal_error;
1570
1571 memcpy ((char *) entries2, (char *) (entries + icount1),
1572 icount2 * sizeof(struct dx_entry));
1573 dx_set_count (entries, icount1);
1574 dx_set_count (entries2, icount2);
1575 dx_set_limit (entries2, dx_node_limit(dir));
1576
1577 /* Which index block gets the new entry? */
1578 if (at - entries >= icount1) {
1579 frame->at = at = at - entries - icount1 + entries2;
1580 frame->entries = entries = entries2;
1581 swap(frame->bh, bh2);
1582 }
1583 dx_insert_block (frames + 0, hash2, newblock);
1584 dxtrace(dx_show_index ("node", frames[1].entries));
1585 dxtrace(dx_show_index ("node",
1586 ((struct dx_node *) bh2->b_data)->entries));
1587 err = ext3_journal_dirty_metadata(handle, bh2);
1588 if (err)
1589 goto journal_error;
1590 brelse (bh2);
1591 } else {
1592 dxtrace(printk("Creating second level index...\n"));
1593 memcpy((char *) entries2, (char *) entries,
1594 icount * sizeof(struct dx_entry));
1595 dx_set_limit(entries2, dx_node_limit(dir));
1596
1597 /* Set up root */
1598 dx_set_count(entries, 1);
1599 dx_set_block(entries + 0, newblock);
1600 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
1601
1602 /* Add new access path frame */
1603 frame = frames + 1;
1604 frame->at = at = at - entries + entries2;
1605 frame->entries = entries = entries2;
1606 frame->bh = bh2;
1607 err = ext3_journal_get_write_access(handle,
1608 frame->bh);
1609 if (err)
1610 goto journal_error;
1611 }
1612 ext3_journal_dirty_metadata(handle, frames[0].bh);
1613 }
1614 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
1615 if (!de)
1616 goto cleanup;
1617 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
1618 bh = NULL;
1619 goto cleanup;
1620
1621journal_error:
1622 ext3_std_error(dir->i_sb, err);
1623cleanup:
1624 if (bh)
1625 brelse(bh);
1626 dx_release(frames);
1627 return err;
1628}
1da177e4
LT
1629
1630/*
1631 * ext3_delete_entry deletes a directory entry by merging it with the
1632 * previous entry
1633 */
ae6ddcc5 1634static int ext3_delete_entry (handle_t *handle,
1da177e4
LT
1635 struct inode * dir,
1636 struct ext3_dir_entry_2 * de_del,
1637 struct buffer_head * bh)
1638{
1639 struct ext3_dir_entry_2 * de, * pde;
1640 int i;
1641
1642 i = 0;
1643 pde = NULL;
1644 de = (struct ext3_dir_entry_2 *) bh->b_data;
1645 while (i < bh->b_size) {
1646 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i))
1647 return -EIO;
1648 if (de == de_del) {
1649 BUFFER_TRACE(bh, "get_write_access");
1650 ext3_journal_get_write_access(handle, bh);
1651 if (pde)
7c06a8dc
JK
1652 pde->rec_len = ext3_rec_len_to_disk(
1653 ext3_rec_len_from_disk(pde->rec_len) +
1654 ext3_rec_len_from_disk(de->rec_len));
1da177e4
LT
1655 else
1656 de->inode = 0;
1657 dir->i_version++;
1658 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1659 ext3_journal_dirty_metadata(handle, bh);
1660 return 0;
1661 }
7c06a8dc 1662 i += ext3_rec_len_from_disk(de->rec_len);
1da177e4 1663 pde = de;
7c06a8dc 1664 de = ext3_next_entry(de);
1da177e4
LT
1665 }
1666 return -ENOENT;
1667}
1668
1da177e4
LT
1669static int ext3_add_nondir(handle_t *handle,
1670 struct dentry *dentry, struct inode *inode)
1671{
1672 int err = ext3_add_entry(handle, dentry, inode);
1673 if (!err) {
1674 ext3_mark_inode_dirty(handle, inode);
1675 d_instantiate(dentry, inode);
1676 return 0;
1677 }
731b9a54 1678 drop_nlink(inode);
1da177e4
LT
1679 iput(inode);
1680 return err;
1681}
1682
1683/*
1684 * By the time this is called, we already have created
1685 * the directory cache entry for the new file, but it
1686 * is so far negative - it has no inode.
1687 *
1688 * If the create succeeds, we fill in the inode information
ae6ddcc5 1689 * with d_instantiate().
1da177e4
LT
1690 */
1691static int ext3_create (struct inode * dir, struct dentry * dentry, int mode,
1692 struct nameidata *nd)
1693{
ae6ddcc5 1694 handle_t *handle;
1da177e4
LT
1695 struct inode * inode;
1696 int err, retries = 0;
1697
1698retry:
1f54587b 1699 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
1da177e4 1700 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1f54587b 1701 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
1da177e4
LT
1702 if (IS_ERR(handle))
1703 return PTR_ERR(handle);
1704
1705 if (IS_DIRSYNC(dir))
1706 handle->h_sync = 1;
1707
1708 inode = ext3_new_inode (handle, dir, mode);
1709 err = PTR_ERR(inode);
1710 if (!IS_ERR(inode)) {
1711 inode->i_op = &ext3_file_inode_operations;
1712 inode->i_fop = &ext3_file_operations;
1713 ext3_set_aops(inode);
1714 err = ext3_add_nondir(handle, dentry, inode);
1715 }
1716 ext3_journal_stop(handle);
1717 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1718 goto retry;
1719 return err;
1720}
1721
1722static int ext3_mknod (struct inode * dir, struct dentry *dentry,
1723 int mode, dev_t rdev)
1724{
1725 handle_t *handle;
1726 struct inode *inode;
1727 int err, retries = 0;
1728
1729 if (!new_valid_dev(rdev))
1730 return -EINVAL;
1731
1732retry:
1f54587b 1733 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
e9ad5620 1734 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1f54587b 1735 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
1da177e4
LT
1736 if (IS_ERR(handle))
1737 return PTR_ERR(handle);
1738
1739 if (IS_DIRSYNC(dir))
1740 handle->h_sync = 1;
1741
1742 inode = ext3_new_inode (handle, dir, mode);
1743 err = PTR_ERR(inode);
1744 if (!IS_ERR(inode)) {
1745 init_special_inode(inode, inode->i_mode, rdev);
1746#ifdef CONFIG_EXT3_FS_XATTR
1747 inode->i_op = &ext3_special_inode_operations;
1748#endif
1749 err = ext3_add_nondir(handle, dentry, inode);
1750 }
1751 ext3_journal_stop(handle);
1752 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1753 goto retry;
1754 return err;
1755}
1756
1757static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode)
1758{
1759 handle_t *handle;
1760 struct inode * inode;
1761 struct buffer_head * dir_block;
1762 struct ext3_dir_entry_2 * de;
1763 int err, retries = 0;
1764
1765 if (dir->i_nlink >= EXT3_LINK_MAX)
1766 return -EMLINK;
1767
1768retry:
1f54587b 1769 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
1da177e4 1770 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1f54587b 1771 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
1da177e4
LT
1772 if (IS_ERR(handle))
1773 return PTR_ERR(handle);
1774
1775 if (IS_DIRSYNC(dir))
1776 handle->h_sync = 1;
1777
1778 inode = ext3_new_inode (handle, dir, S_IFDIR | mode);
1779 err = PTR_ERR(inode);
1780 if (IS_ERR(inode))
1781 goto out_stop;
1782
1783 inode->i_op = &ext3_dir_inode_operations;
1784 inode->i_fop = &ext3_dir_operations;
1785 inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1786 dir_block = ext3_bread (handle, inode, 0, 1, &err);
1787 if (!dir_block) {
9a53c3a7 1788 drop_nlink(inode); /* is this nlink == 0? */
1da177e4
LT
1789 ext3_mark_inode_dirty(handle, inode);
1790 iput (inode);
1791 goto out_stop;
1792 }
1793 BUFFER_TRACE(dir_block, "get_write_access");
1794 ext3_journal_get_write_access(handle, dir_block);
1795 de = (struct ext3_dir_entry_2 *) dir_block->b_data;
1796 de->inode = cpu_to_le32(inode->i_ino);
1797 de->name_len = 1;
7c06a8dc 1798 de->rec_len = ext3_rec_len_to_disk(EXT3_DIR_REC_LEN(de->name_len));
1da177e4
LT
1799 strcpy (de->name, ".");
1800 ext3_set_de_type(dir->i_sb, de, S_IFDIR);
7c06a8dc 1801 de = ext3_next_entry(de);
1da177e4 1802 de->inode = cpu_to_le32(dir->i_ino);
7c06a8dc
JK
1803 de->rec_len = ext3_rec_len_to_disk(inode->i_sb->s_blocksize -
1804 EXT3_DIR_REC_LEN(1));
1da177e4
LT
1805 de->name_len = 2;
1806 strcpy (de->name, "..");
1807 ext3_set_de_type(dir->i_sb, de, S_IFDIR);
1808 inode->i_nlink = 2;
1809 BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata");
1810 ext3_journal_dirty_metadata(handle, dir_block);
1811 brelse (dir_block);
1812 ext3_mark_inode_dirty(handle, inode);
1813 err = ext3_add_entry (handle, dentry, inode);
1814 if (err) {
1815 inode->i_nlink = 0;
1816 ext3_mark_inode_dirty(handle, inode);
1817 iput (inode);
1818 goto out_stop;
1819 }
d8c76e6f 1820 inc_nlink(dir);
1da177e4
LT
1821 ext3_update_dx_flag(dir);
1822 ext3_mark_inode_dirty(handle, dir);
1823 d_instantiate(dentry, inode);
1824out_stop:
1825 ext3_journal_stop(handle);
1826 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1827 goto retry;
1828 return err;
1829}
1830
1831/*
1832 * routine to check that the specified directory is empty (for rmdir)
1833 */
1834static int empty_dir (struct inode * inode)
1835{
1836 unsigned long offset;
1837 struct buffer_head * bh;
1838 struct ext3_dir_entry_2 * de, * de1;
1839 struct super_block * sb;
1840 int err = 0;
1841
1842 sb = inode->i_sb;
1843 if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) ||
1844 !(bh = ext3_bread (NULL, inode, 0, 0, &err))) {
1845 if (err)
1846 ext3_error(inode->i_sb, __FUNCTION__,
1847 "error %d reading directory #%lu offset 0",
1848 err, inode->i_ino);
1849 else
1850 ext3_warning(inode->i_sb, __FUNCTION__,
1851 "bad directory (dir #%lu) - no data block",
1852 inode->i_ino);
1853 return 1;
1854 }
1855 de = (struct ext3_dir_entry_2 *) bh->b_data;
7c06a8dc 1856 de1 = ext3_next_entry(de);
1da177e4 1857 if (le32_to_cpu(de->inode) != inode->i_ino ||
ae6ddcc5 1858 !le32_to_cpu(de1->inode) ||
1da177e4
LT
1859 strcmp (".", de->name) ||
1860 strcmp ("..", de1->name)) {
e9ad5620 1861 ext3_warning (inode->i_sb, "empty_dir",
1da177e4
LT
1862 "bad directory (dir #%lu) - no `.' or `..'",
1863 inode->i_ino);
1864 brelse (bh);
1865 return 1;
1866 }
7c06a8dc
JK
1867 offset = ext3_rec_len_from_disk(de->rec_len) +
1868 ext3_rec_len_from_disk(de1->rec_len);
1869 de = ext3_next_entry(de1);
1da177e4
LT
1870 while (offset < inode->i_size ) {
1871 if (!bh ||
1872 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
1873 err = 0;
1874 brelse (bh);
1875 bh = ext3_bread (NULL, inode,
1876 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err);
1877 if (!bh) {
1878 if (err)
1879 ext3_error(sb, __FUNCTION__,
1880 "error %d reading directory"
1881 " #%lu offset %lu",
1882 err, inode->i_ino, offset);
1883 offset += sb->s_blocksize;
1884 continue;
1885 }
1886 de = (struct ext3_dir_entry_2 *) bh->b_data;
1887 }
1888 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) {
1889 de = (struct ext3_dir_entry_2 *)(bh->b_data +
1890 sb->s_blocksize);
1891 offset = (offset | (sb->s_blocksize - 1)) + 1;
1892 continue;
1893 }
1894 if (le32_to_cpu(de->inode)) {
1895 brelse (bh);
1896 return 0;
1897 }
7c06a8dc
JK
1898 offset += ext3_rec_len_from_disk(de->rec_len);
1899 de = ext3_next_entry(de);
1da177e4
LT
1900 }
1901 brelse (bh);
1902 return 1;
1903}
1904
1905/* ext3_orphan_add() links an unlinked or truncated inode into a list of
1906 * such inodes, starting at the superblock, in case we crash before the
1907 * file is closed/deleted, or in case the inode truncate spans multiple
1908 * transactions and the last transaction is not recovered after a crash.
1909 *
1910 * At filesystem recovery time, we walk this list deleting unlinked
1911 * inodes and truncating linked inodes in ext3_orphan_cleanup().
1912 */
1913int ext3_orphan_add(handle_t *handle, struct inode *inode)
1914{
1915 struct super_block *sb = inode->i_sb;
1916 struct ext3_iloc iloc;
1917 int err = 0, rc;
1918
1919 lock_super(sb);
1920 if (!list_empty(&EXT3_I(inode)->i_orphan))
1921 goto out_unlock;
1922
1923 /* Orphan handling is only valid for files with data blocks
1924 * being truncated, or files being unlinked. */
1925
1926 /* @@@ FIXME: Observation from aviro:
ae6ddcc5 1927 * I think I can trigger J_ASSERT in ext3_orphan_add(). We block
1da177e4
LT
1928 * here (on lock_super()), so race with ext3_link() which might bump
1929 * ->i_nlink. For, say it, character device. Not a regular file,
1930 * not a directory, not a symlink and ->i_nlink > 0.
1931 */
1932 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1933 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
1934
1935 BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access");
1936 err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
1937 if (err)
1938 goto out_unlock;
1939
1940 err = ext3_reserve_inode_write(handle, inode, &iloc);
1941 if (err)
1942 goto out_unlock;
1943
1944 /* Insert this inode at the head of the on-disk orphan list... */
1945 NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan);
1946 EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
1947 err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
1948 rc = ext3_mark_iloc_dirty(handle, inode, &iloc);
1949 if (!err)
1950 err = rc;
1951
1952 /* Only add to the head of the in-memory list if all the
1953 * previous operations succeeded. If the orphan_add is going to
1954 * fail (possibly taking the journal offline), we can't risk
1955 * leaving the inode on the orphan list: stray orphan-list
1956 * entries can cause panics at unmount time.
1957 *
1958 * This is safe: on error we're going to ignore the orphan list
1959 * anyway on the next recovery. */
1960 if (!err)
1961 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan);
1962
eee194e7
ES
1963 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
1964 jbd_debug(4, "orphan inode %lu will point to %d\n",
1da177e4
LT
1965 inode->i_ino, NEXT_ORPHAN(inode));
1966out_unlock:
1967 unlock_super(sb);
1968 ext3_std_error(inode->i_sb, err);
1969 return err;
1970}
1971
1972/*
1973 * ext3_orphan_del() removes an unlinked or truncated inode from the list
1974 * of such inodes stored on disk, because it is finally being cleaned up.
1975 */
1976int ext3_orphan_del(handle_t *handle, struct inode *inode)
1977{
1978 struct list_head *prev;
1979 struct ext3_inode_info *ei = EXT3_I(inode);
1980 struct ext3_sb_info *sbi;
1981 unsigned long ino_next;
1982 struct ext3_iloc iloc;
1983 int err = 0;
1984
1985 lock_super(inode->i_sb);
1986 if (list_empty(&ei->i_orphan)) {
1987 unlock_super(inode->i_sb);
1988 return 0;
1989 }
1990
1991 ino_next = NEXT_ORPHAN(inode);
1992 prev = ei->i_orphan.prev;
1993 sbi = EXT3_SB(inode->i_sb);
1994
1995 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
1996
1997 list_del_init(&ei->i_orphan);
1998
1999 /* If we're on an error path, we may not have a valid
2000 * transaction handle with which to update the orphan list on
2001 * disk, but we still need to remove the inode from the linked
2002 * list in memory. */
2003 if (!handle)
2004 goto out;
2005
2006 err = ext3_reserve_inode_write(handle, inode, &iloc);
2007 if (err)
2008 goto out_err;
2009
2010 if (prev == &sbi->s_orphan) {
2011 jbd_debug(4, "superblock will point to %lu\n", ino_next);
2012 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
2013 err = ext3_journal_get_write_access(handle, sbi->s_sbh);
2014 if (err)
2015 goto out_brelse;
2016 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
2017 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
2018 } else {
2019 struct ext3_iloc iloc2;
2020 struct inode *i_prev =
2021 &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode;
2022
2023 jbd_debug(4, "orphan inode %lu will point to %lu\n",
2024 i_prev->i_ino, ino_next);
2025 err = ext3_reserve_inode_write(handle, i_prev, &iloc2);
2026 if (err)
2027 goto out_brelse;
2028 NEXT_ORPHAN(i_prev) = ino_next;
2029 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2);
2030 }
2031 if (err)
2032 goto out_brelse;
2033 NEXT_ORPHAN(inode) = 0;
2034 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
2035
2036out_err:
2037 ext3_std_error(inode->i_sb, err);
2038out:
2039 unlock_super(inode->i_sb);
2040 return err;
2041
2042out_brelse:
2043 brelse(iloc.bh);
2044 goto out_err;
2045}
2046
2047static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
2048{
2049 int retval;
2050 struct inode * inode;
2051 struct buffer_head * bh;
2052 struct ext3_dir_entry_2 * de;
2053 handle_t *handle;
2054
2055 /* Initialize quotas before so that eventual writes go in
2056 * separate transaction */
2057 DQUOT_INIT(dentry->d_inode);
1f54587b 2058 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
1da177e4
LT
2059 if (IS_ERR(handle))
2060 return PTR_ERR(handle);
2061
2062 retval = -ENOENT;
2063 bh = ext3_find_entry (dentry, &de);
2064 if (!bh)
2065 goto end_rmdir;
2066
2067 if (IS_DIRSYNC(dir))
2068 handle->h_sync = 1;
2069
2070 inode = dentry->d_inode;
2071
2072 retval = -EIO;
2073 if (le32_to_cpu(de->inode) != inode->i_ino)
2074 goto end_rmdir;
2075
2076 retval = -ENOTEMPTY;
2077 if (!empty_dir (inode))
2078 goto end_rmdir;
2079
2080 retval = ext3_delete_entry(handle, dir, de, bh);
2081 if (retval)
2082 goto end_rmdir;
2083 if (inode->i_nlink != 2)
2084 ext3_warning (inode->i_sb, "ext3_rmdir",
2085 "empty directory has nlink!=2 (%d)",
2086 inode->i_nlink);
2087 inode->i_version++;
ce71ec36 2088 clear_nlink(inode);
1da177e4
LT
2089 /* There's no need to set i_disksize: the fact that i_nlink is
2090 * zero will ensure that the right thing happens during any
2091 * recovery. */
2092 inode->i_size = 0;
2093 ext3_orphan_add(handle, inode);
2094 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
2095 ext3_mark_inode_dirty(handle, inode);
9a53c3a7 2096 drop_nlink(dir);
1da177e4
LT
2097 ext3_update_dx_flag(dir);
2098 ext3_mark_inode_dirty(handle, dir);
2099
2100end_rmdir:
2101 ext3_journal_stop(handle);
2102 brelse (bh);
2103 return retval;
2104}
2105
2106static int ext3_unlink(struct inode * dir, struct dentry *dentry)
2107{
2108 int retval;
2109 struct inode * inode;
2110 struct buffer_head * bh;
2111 struct ext3_dir_entry_2 * de;
2112 handle_t *handle;
2113
2114 /* Initialize quotas before so that eventual writes go
2115 * in separate transaction */
2116 DQUOT_INIT(dentry->d_inode);
1f54587b 2117 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
1da177e4
LT
2118 if (IS_ERR(handle))
2119 return PTR_ERR(handle);
2120
2121 if (IS_DIRSYNC(dir))
2122 handle->h_sync = 1;
2123
2124 retval = -ENOENT;
2125 bh = ext3_find_entry (dentry, &de);
2126 if (!bh)
2127 goto end_unlink;
2128
2129 inode = dentry->d_inode;
2130
2131 retval = -EIO;
2132 if (le32_to_cpu(de->inode) != inode->i_ino)
2133 goto end_unlink;
2134
2135 if (!inode->i_nlink) {
2136 ext3_warning (inode->i_sb, "ext3_unlink",
2137 "Deleting nonexistent file (%lu), %d",
2138 inode->i_ino, inode->i_nlink);
2139 inode->i_nlink = 1;
2140 }
2141 retval = ext3_delete_entry(handle, dir, de, bh);
2142 if (retval)
2143 goto end_unlink;
2144 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
2145 ext3_update_dx_flag(dir);
2146 ext3_mark_inode_dirty(handle, dir);
9a53c3a7 2147 drop_nlink(inode);
1da177e4
LT
2148 if (!inode->i_nlink)
2149 ext3_orphan_add(handle, inode);
2150 inode->i_ctime = dir->i_ctime;
2151 ext3_mark_inode_dirty(handle, inode);
2152 retval = 0;
2153
2154end_unlink:
2155 ext3_journal_stop(handle);
2156 brelse (bh);
2157 return retval;
2158}
2159
2160static int ext3_symlink (struct inode * dir,
2161 struct dentry *dentry, const char * symname)
2162{
2163 handle_t *handle;
2164 struct inode * inode;
2165 int l, err, retries = 0;
2166
2167 l = strlen(symname)+1;
2168 if (l > dir->i_sb->s_blocksize)
2169 return -ENAMETOOLONG;
2170
2171retry:
1f54587b 2172 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
e9ad5620 2173 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 +
1f54587b 2174 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
1da177e4
LT
2175 if (IS_ERR(handle))
2176 return PTR_ERR(handle);
2177
2178 if (IS_DIRSYNC(dir))
2179 handle->h_sync = 1;
2180
2181 inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
2182 err = PTR_ERR(inode);
2183 if (IS_ERR(inode))
2184 goto out_stop;
2185
2186 if (l > sizeof (EXT3_I(inode)->i_data)) {
2187 inode->i_op = &ext3_symlink_inode_operations;
2188 ext3_set_aops(inode);
2189 /*
2190 * page_symlink() calls into ext3_prepare/commit_write.
2191 * We have a transaction open. All is sweetness. It also sets
2192 * i_size in generic_commit_write().
2193 */
0adb25d2
KK
2194 err = __page_symlink(inode, symname, l,
2195 mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
1da177e4 2196 if (err) {
731b9a54 2197 drop_nlink(inode);
1da177e4
LT
2198 ext3_mark_inode_dirty(handle, inode);
2199 iput (inode);
2200 goto out_stop;
2201 }
2202 } else {
2203 inode->i_op = &ext3_fast_symlink_inode_operations;
2204 memcpy((char*)&EXT3_I(inode)->i_data,symname,l);
2205 inode->i_size = l-1;
2206 }
2207 EXT3_I(inode)->i_disksize = inode->i_size;
2208 err = ext3_add_nondir(handle, dentry, inode);
2209out_stop:
2210 ext3_journal_stop(handle);
2211 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
2212 goto retry;
2213 return err;
2214}
2215
2216static int ext3_link (struct dentry * old_dentry,
2217 struct inode * dir, struct dentry *dentry)
2218{
2219 handle_t *handle;
2220 struct inode *inode = old_dentry->d_inode;
2221 int err, retries = 0;
2222
2223 if (inode->i_nlink >= EXT3_LINK_MAX)
2224 return -EMLINK;
2988a774
ES
2225 /*
2226 * Return -ENOENT if we've raced with unlink and i_nlink is 0. Doing
2227 * otherwise has the potential to corrupt the orphan inode list.
2228 */
2229 if (inode->i_nlink == 0)
2230 return -ENOENT;
1da177e4
LT
2231
2232retry:
1f54587b 2233 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
1da177e4
LT
2234 EXT3_INDEX_EXTRA_TRANS_BLOCKS);
2235 if (IS_ERR(handle))
2236 return PTR_ERR(handle);
2237
2238 if (IS_DIRSYNC(dir))
2239 handle->h_sync = 1;
2240
2241 inode->i_ctime = CURRENT_TIME_SEC;
731b9a54 2242 inc_nlink(inode);
1da177e4
LT
2243 atomic_inc(&inode->i_count);
2244
2245 err = ext3_add_nondir(handle, dentry, inode);
2246 ext3_journal_stop(handle);
2247 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
2248 goto retry;
2249 return err;
2250}
2251
2252#define PARENT_INO(buffer) \
7c06a8dc 2253 (ext3_next_entry((struct ext3_dir_entry_2 *)(buffer))->inode)
1da177e4
LT
2254
2255/*
2256 * Anybody can rename anything with this: the permission checks are left to the
2257 * higher-level routines.
2258 */
2259static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
2260 struct inode * new_dir,struct dentry *new_dentry)
2261{
2262 handle_t *handle;
2263 struct inode * old_inode, * new_inode;
2264 struct buffer_head * old_bh, * new_bh, * dir_bh;
2265 struct ext3_dir_entry_2 * old_de, * new_de;
2266 int retval;
2267
2268 old_bh = new_bh = dir_bh = NULL;
2269
2270 /* Initialize quotas before so that eventual writes go
2271 * in separate transaction */
2272 if (new_dentry->d_inode)
2273 DQUOT_INIT(new_dentry->d_inode);
1f54587b
JK
2274 handle = ext3_journal_start(old_dir, 2 *
2275 EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) +
e9ad5620 2276 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2);
1da177e4
LT
2277 if (IS_ERR(handle))
2278 return PTR_ERR(handle);
2279
2280 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
2281 handle->h_sync = 1;
2282
2283 old_bh = ext3_find_entry (old_dentry, &old_de);
2284 /*
2285 * Check for inode number is _not_ due to possible IO errors.
2286 * We might rmdir the source, keep it as pwd of some process
2287 * and merrily kill the link to whatever was created under the
2288 * same name. Goodbye sticky bit ;-<
2289 */
2290 old_inode = old_dentry->d_inode;
2291 retval = -ENOENT;
2292 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
2293 goto end_rename;
2294
2295 new_inode = new_dentry->d_inode;
2296 new_bh = ext3_find_entry (new_dentry, &new_de);
2297 if (new_bh) {
2298 if (!new_inode) {
2299 brelse (new_bh);
2300 new_bh = NULL;
2301 }
2302 }
2303 if (S_ISDIR(old_inode->i_mode)) {
2304 if (new_inode) {
2305 retval = -ENOTEMPTY;
2306 if (!empty_dir (new_inode))
2307 goto end_rename;
2308 }
2309 retval = -EIO;
2310 dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval);
2311 if (!dir_bh)
2312 goto end_rename;
2313 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
2314 goto end_rename;
2315 retval = -EMLINK;
2316 if (!new_inode && new_dir!=old_dir &&
2317 new_dir->i_nlink >= EXT3_LINK_MAX)
2318 goto end_rename;
2319 }
2320 if (!new_bh) {
2321 retval = ext3_add_entry (handle, new_dentry, old_inode);
2322 if (retval)
2323 goto end_rename;
2324 } else {
2325 BUFFER_TRACE(new_bh, "get write access");
2326 ext3_journal_get_write_access(handle, new_bh);
2327 new_de->inode = cpu_to_le32(old_inode->i_ino);
2328 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
2329 EXT3_FEATURE_INCOMPAT_FILETYPE))
2330 new_de->file_type = old_de->file_type;
2331 new_dir->i_version++;
2332 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata");
2333 ext3_journal_dirty_metadata(handle, new_bh);
2334 brelse(new_bh);
2335 new_bh = NULL;
2336 }
2337
2338 /*
2339 * Like most other Unix systems, set the ctime for inodes on a
2340 * rename.
2341 */
2342 old_inode->i_ctime = CURRENT_TIME_SEC;
2343 ext3_mark_inode_dirty(handle, old_inode);
2344
2345 /*
2346 * ok, that's it
2347 */
2348 if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
2349 old_de->name_len != old_dentry->d_name.len ||
2350 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
2351 (retval = ext3_delete_entry(handle, old_dir,
2352 old_de, old_bh)) == -ENOENT) {
2353 /* old_de could have moved from under us during htree split, so
2354 * make sure that we are deleting the right entry. We might
2355 * also be pointing to a stale entry in the unused part of
2356 * old_bh so just checking inum and the name isn't enough. */
2357 struct buffer_head *old_bh2;
2358 struct ext3_dir_entry_2 *old_de2;
2359
2360 old_bh2 = ext3_find_entry(old_dentry, &old_de2);
2361 if (old_bh2) {
2362 retval = ext3_delete_entry(handle, old_dir,
2363 old_de2, old_bh2);
2364 brelse(old_bh2);
2365 }
2366 }
2367 if (retval) {
2368 ext3_warning(old_dir->i_sb, "ext3_rename",
2369 "Deleting old file (%lu), %d, error=%d",
2370 old_dir->i_ino, old_dir->i_nlink, retval);
2371 }
2372
2373 if (new_inode) {
9a53c3a7 2374 drop_nlink(new_inode);
1da177e4
LT
2375 new_inode->i_ctime = CURRENT_TIME_SEC;
2376 }
2377 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
2378 ext3_update_dx_flag(old_dir);
2379 if (dir_bh) {
2380 BUFFER_TRACE(dir_bh, "get_write_access");
2381 ext3_journal_get_write_access(handle, dir_bh);
2382 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
2383 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata");
2384 ext3_journal_dirty_metadata(handle, dir_bh);
9a53c3a7 2385 drop_nlink(old_dir);
1da177e4 2386 if (new_inode) {
9a53c3a7 2387 drop_nlink(new_inode);
1da177e4 2388 } else {
d8c76e6f 2389 inc_nlink(new_dir);
1da177e4
LT
2390 ext3_update_dx_flag(new_dir);
2391 ext3_mark_inode_dirty(handle, new_dir);
2392 }
2393 }
2394 ext3_mark_inode_dirty(handle, old_dir);
2395 if (new_inode) {
2396 ext3_mark_inode_dirty(handle, new_inode);
2397 if (!new_inode->i_nlink)
2398 ext3_orphan_add(handle, new_inode);
2399 }
2400 retval = 0;
2401
2402end_rename:
2403 brelse (dir_bh);
2404 brelse (old_bh);
2405 brelse (new_bh);
2406 ext3_journal_stop(handle);
2407 return retval;
2408}
2409
2410/*
2411 * directories can handle most operations...
2412 */
754661f1 2413const struct inode_operations ext3_dir_inode_operations = {
1da177e4
LT
2414 .create = ext3_create,
2415 .lookup = ext3_lookup,
2416 .link = ext3_link,
2417 .unlink = ext3_unlink,
2418 .symlink = ext3_symlink,
2419 .mkdir = ext3_mkdir,
2420 .rmdir = ext3_rmdir,
2421 .mknod = ext3_mknod,
2422 .rename = ext3_rename,
2423 .setattr = ext3_setattr,
2424#ifdef CONFIG_EXT3_FS_XATTR
2425 .setxattr = generic_setxattr,
2426 .getxattr = generic_getxattr,
2427 .listxattr = ext3_listxattr,
2428 .removexattr = generic_removexattr,
2429#endif
2430 .permission = ext3_permission,
2431};
2432
754661f1 2433const struct inode_operations ext3_special_inode_operations = {
1da177e4
LT
2434 .setattr = ext3_setattr,
2435#ifdef CONFIG_EXT3_FS_XATTR
2436 .setxattr = generic_setxattr,
2437 .getxattr = generic_getxattr,
2438 .listxattr = ext3_listxattr,
2439 .removexattr = generic_removexattr,
2440#endif
2441 .permission = ext3_permission,
ae6ddcc5 2442};
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