blob: af193a304ee5868c6bd54db9f8018159940463bb [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
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>
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>
38#include <linux/smp_lock.h>
Ben Dooks381be2542005-10-30 15:02:56 -080039
40#include "namei.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#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
79#define dxtrace(command)
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;
143 u32 offs;
144};
145
146#ifdef CONFIG_EXT3_INDEX
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,
172 struct dx_frame *frames,
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
179/*
180 * Future: use high four bits of block for coalesce-on-delete flags
181 * Mask them off for now.
182 */
183
184static inline unsigned dx_get_block (struct dx_entry *entry)
185{
186 return le32_to_cpu(entry->block) & 0x00ffffff;
187}
188
189static inline void dx_set_block (struct dx_entry *entry, unsigned value)
190{
191 entry->block = cpu_to_le32(value);
192}
193
194static inline unsigned dx_get_hash (struct dx_entry *entry)
195{
196 return le32_to_cpu(entry->hash);
197}
198
199static inline void dx_set_hash (struct dx_entry *entry, unsigned value)
200{
201 entry->hash = cpu_to_le32(value);
202}
203
204static inline unsigned dx_get_count (struct dx_entry *entries)
205{
206 return le16_to_cpu(((struct dx_countlimit *) entries)->count);
207}
208
209static inline unsigned dx_get_limit (struct dx_entry *entries)
210{
211 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
212}
213
214static inline void dx_set_count (struct dx_entry *entries, unsigned value)
215{
216 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
217}
218
219static inline void dx_set_limit (struct dx_entry *entries, unsigned value)
220{
221 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
222}
223
224static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
225{
226 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) -
227 EXT3_DIR_REC_LEN(2) - infosize;
228 return 0? 20: entry_space / sizeof(struct dx_entry);
229}
230
231static inline unsigned dx_node_limit (struct inode *dir)
232{
233 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0);
234 return 0? 22: entry_space / sizeof(struct dx_entry);
235}
236
237/*
238 * Debug
239 */
240#ifdef DX_DEBUG
241static void dx_show_index (char * label, struct dx_entry *entries)
242{
243 int i, n = dx_get_count (entries);
244 printk("%s index ", label);
245 for (i = 0; i < n; i++)
246 {
247 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i));
248 }
249 printk("\n");
250}
251
252struct stats
253{
254 unsigned names;
255 unsigned space;
256 unsigned bcount;
257};
258
259static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de,
260 int size, int show_names)
261{
262 unsigned names = 0, space = 0;
263 char *base = (char *) de;
264 struct dx_hash_info h = *hinfo;
265
266 printk("names: ");
267 while ((char *) de < base + size)
268 {
269 if (de->inode)
270 {
271 if (show_names)
272 {
273 int len = de->name_len;
274 char *name = de->name;
275 while (len--) printk("%c", *name++);
276 ext3fs_dirhash(de->name, de->name_len, &h);
277 printk(":%x.%u ", h.hash,
278 ((char *) de - base));
279 }
280 space += EXT3_DIR_REC_LEN(de->name_len);
281 names++;
282 }
283 de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
284 }
285 printk("(%i)\n", names);
286 return (struct stats) { names, space, 1 };
287}
288
289struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
290 struct dx_entry *entries, int levels)
291{
292 unsigned blocksize = dir->i_sb->s_blocksize;
293 unsigned count = dx_get_count (entries), names = 0, space = 0, i;
294 unsigned bcount = 0;
295 struct buffer_head *bh;
296 int err;
297 printk("%i indexed blocks...\n", count);
298 for (i = 0; i < count; i++, entries++)
299 {
300 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0;
301 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
302 struct stats stats;
303 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
304 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue;
305 stats = levels?
306 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
307 dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0);
308 names += stats.names;
309 space += stats.space;
310 bcount += stats.bcount;
311 brelse (bh);
312 }
313 if (bcount)
314 printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ",
315 names, space/bcount,(space/bcount)*100/blocksize);
316 return (struct stats) { names, space, bcount};
317}
318#endif /* DX_DEBUG */
319
320/*
321 * Probe for a directory leaf block to search.
322 *
323 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
324 * error in the directory index, and the caller should fall back to
325 * searching the directory normally. The callers of dx_probe **MUST**
326 * check for this error code, and make sure it never gets reflected
327 * back to userspace.
328 */
329static struct dx_frame *
330dx_probe(struct dentry *dentry, struct inode *dir,
331 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
332{
333 unsigned count, indirect;
334 struct dx_entry *at, *entries, *p, *q, *m;
335 struct dx_root *root;
336 struct buffer_head *bh;
337 struct dx_frame *frame = frame_in;
338 u32 hash;
339
340 frame->bh = NULL;
341 if (dentry)
342 dir = dentry->d_parent->d_inode;
343 if (!(bh = ext3_bread (NULL,dir, 0, 0, err)))
344 goto fail;
345 root = (struct dx_root *) bh->b_data;
346 if (root->info.hash_version != DX_HASH_TEA &&
347 root->info.hash_version != DX_HASH_HALF_MD4 &&
348 root->info.hash_version != DX_HASH_LEGACY) {
349 ext3_warning(dir->i_sb, __FUNCTION__,
350 "Unrecognised inode hash code %d",
351 root->info.hash_version);
352 brelse(bh);
353 *err = ERR_BAD_DX_DIR;
354 goto fail;
355 }
356 hinfo->hash_version = root->info.hash_version;
357 hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed;
358 if (dentry)
359 ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo);
360 hash = hinfo->hash;
361
362 if (root->info.unused_flags & 1) {
363 ext3_warning(dir->i_sb, __FUNCTION__,
364 "Unimplemented inode hash flags: %#06x",
365 root->info.unused_flags);
366 brelse(bh);
367 *err = ERR_BAD_DX_DIR;
368 goto fail;
369 }
370
371 if ((indirect = root->info.indirect_levels) > 1) {
372 ext3_warning(dir->i_sb, __FUNCTION__,
373 "Unimplemented inode hash depth: %#06x",
374 root->info.indirect_levels);
375 brelse(bh);
376 *err = ERR_BAD_DX_DIR;
377 goto fail;
378 }
379
380 entries = (struct dx_entry *) (((char *)&root->info) +
381 root->info.info_length);
382 assert(dx_get_limit(entries) == dx_root_limit(dir,
383 root->info.info_length));
384 dxtrace (printk("Look up %x", hash));
385 while (1)
386 {
387 count = dx_get_count(entries);
388 assert (count && count <= dx_get_limit(entries));
389 p = entries + 1;
390 q = entries + count - 1;
391 while (p <= q)
392 {
393 m = p + (q - p)/2;
394 dxtrace(printk("."));
395 if (dx_get_hash(m) > hash)
396 q = m - 1;
397 else
398 p = m + 1;
399 }
400
401 if (0) // linear search cross check
402 {
403 unsigned n = count - 1;
404 at = entries;
405 while (n--)
406 {
407 dxtrace(printk(","));
408 if (dx_get_hash(++at) > hash)
409 {
410 at--;
411 break;
412 }
413 }
414 assert (at == p - 1);
415 }
416
417 at = p - 1;
418 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
419 frame->bh = bh;
420 frame->entries = entries;
421 frame->at = at;
422 if (!indirect--) return frame;
423 if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err)))
424 goto fail2;
425 at = entries = ((struct dx_node *) bh->b_data)->entries;
426 assert (dx_get_limit(entries) == dx_node_limit (dir));
427 frame++;
428 }
429fail2:
430 while (frame >= frame_in) {
431 brelse(frame->bh);
432 frame--;
433 }
434fail:
435 return NULL;
436}
437
438static void dx_release (struct dx_frame *frames)
439{
440 if (frames[0].bh == NULL)
441 return;
442
443 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
444 brelse(frames[1].bh);
445 brelse(frames[0].bh);
446}
447
448/*
449 * This function increments the frame pointer to search the next leaf
450 * block, and reads in the necessary intervening nodes if the search
451 * should be necessary. Whether or not the search is necessary is
452 * controlled by the hash parameter. If the hash value is even, then
453 * the search is only continued if the next block starts with that
454 * hash value. This is used if we are searching for a specific file.
455 *
456 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
457 *
458 * This function returns 1 if the caller should continue to search,
459 * or 0 if it should not. If there is an error reading one of the
460 * index blocks, it will a negative error code.
461 *
462 * If start_hash is non-null, it will be filled in with the starting
463 * hash of the next page.
464 */
465static int ext3_htree_next_block(struct inode *dir, __u32 hash,
466 struct dx_frame *frame,
467 struct dx_frame *frames,
468 __u32 *start_hash)
469{
470 struct dx_frame *p;
471 struct buffer_head *bh;
472 int err, num_frames = 0;
473 __u32 bhash;
474
475 p = frame;
476 /*
477 * Find the next leaf page by incrementing the frame pointer.
478 * If we run out of entries in the interior node, loop around and
479 * increment pointer in the parent node. When we break out of
480 * this loop, num_frames indicates the number of interior
481 * nodes need to be read.
482 */
483 while (1) {
484 if (++(p->at) < p->entries + dx_get_count(p->entries))
485 break;
486 if (p == frames)
487 return 0;
488 num_frames++;
489 p--;
490 }
491
492 /*
493 * If the hash is 1, then continue only if the next page has a
494 * continuation hash of any value. This is used for readdir
495 * handling. Otherwise, check to see if the hash matches the
496 * desired contiuation hash. If it doesn't, return since
497 * there's no point to read in the successive index pages.
498 */
499 bhash = dx_get_hash(p->at);
500 if (start_hash)
501 *start_hash = bhash;
502 if ((hash & 1) == 0) {
503 if ((bhash & ~1) != hash)
504 return 0;
505 }
506 /*
507 * If the hash is HASH_NB_ALWAYS, we always go to the next
508 * block so no check is necessary
509 */
510 while (num_frames--) {
511 if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at),
512 0, &err)))
513 return err; /* Failure */
514 p++;
515 brelse (p->bh);
516 p->bh = bh;
517 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
518 }
519 return 1;
520}
521
522
523/*
524 * p is at least 6 bytes before the end of page
525 */
526static inline struct ext3_dir_entry_2 *ext3_next_entry(struct ext3_dir_entry_2 *p)
527{
528 return (struct ext3_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len));
529}
530
531/*
532 * This function fills a red-black tree with information from a
533 * directory block. It returns the number directory entries loaded
534 * into the tree. If there is an error it is returned in err.
535 */
536static int htree_dirblock_to_tree(struct file *dir_file,
537 struct inode *dir, int block,
538 struct dx_hash_info *hinfo,
539 __u32 start_hash, __u32 start_minor_hash)
540{
541 struct buffer_head *bh;
542 struct ext3_dir_entry_2 *de, *top;
543 int err, count = 0;
544
545 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
546 if (!(bh = ext3_bread (NULL, dir, block, 0, &err)))
547 return err;
548
549 de = (struct ext3_dir_entry_2 *) bh->b_data;
550 top = (struct ext3_dir_entry_2 *) ((char *) de +
551 dir->i_sb->s_blocksize -
552 EXT3_DIR_REC_LEN(0));
553 for (; de < top; de = ext3_next_entry(de)) {
554 ext3fs_dirhash(de->name, de->name_len, hinfo);
555 if ((hinfo->hash < start_hash) ||
556 ((hinfo->hash == start_hash) &&
557 (hinfo->minor_hash < start_minor_hash)))
558 continue;
559 if (de->inode == 0)
560 continue;
561 if ((err = ext3_htree_store_dirent(dir_file,
562 hinfo->hash, hinfo->minor_hash, de)) != 0) {
563 brelse(bh);
564 return err;
565 }
566 count++;
567 }
568 brelse(bh);
569 return count;
570}
571
572
573/*
574 * This function fills a red-black tree with information from a
575 * directory. We start scanning the directory in hash order, starting
576 * at start_hash and start_minor_hash.
577 *
578 * This function returns the number of entries inserted into the tree,
579 * or a negative error code.
580 */
581int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
582 __u32 start_minor_hash, __u32 *next_hash)
583{
584 struct dx_hash_info hinfo;
585 struct ext3_dir_entry_2 *de;
586 struct dx_frame frames[2], *frame;
587 struct inode *dir;
588 int block, err;
589 int count = 0;
590 int ret;
591 __u32 hashval;
592
593 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
594 start_minor_hash));
595 dir = dir_file->f_dentry->d_inode;
596 if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) {
597 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
598 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
599 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
600 start_hash, start_minor_hash);
601 *next_hash = ~0;
602 return count;
603 }
604 hinfo.hash = start_hash;
605 hinfo.minor_hash = 0;
606 frame = dx_probe(NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err);
607 if (!frame)
608 return err;
609
610 /* Add '.' and '..' from the htree header */
611 if (!start_hash && !start_minor_hash) {
612 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
613 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0)
614 goto errout;
615 count++;
616 }
617 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
618 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
619 de = ext3_next_entry(de);
620 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0)
621 goto errout;
622 count++;
623 }
624
625 while (1) {
626 block = dx_get_block(frame->at);
627 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
628 start_hash, start_minor_hash);
629 if (ret < 0) {
630 err = ret;
631 goto errout;
632 }
633 count += ret;
634 hashval = ~0;
635 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS,
636 frame, frames, &hashval);
637 *next_hash = hashval;
638 if (ret < 0) {
639 err = ret;
640 goto errout;
641 }
642 /*
643 * Stop if: (a) there are no more entries, or
644 * (b) we have inserted at least one entry and the
645 * next hash value is not a continuation
646 */
647 if ((ret == 0) ||
648 (count && ((hashval & 1) == 0)))
649 break;
650 }
651 dx_release(frames);
652 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n",
653 count, *next_hash));
654 return count;
655errout:
656 dx_release(frames);
657 return (err);
658}
659
660
661/*
662 * Directory block splitting, compacting
663 */
664
665static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
666 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
667{
668 int count = 0;
669 char *base = (char *) de;
670 struct dx_hash_info h = *hinfo;
671
672 while ((char *) de < base + size)
673 {
674 if (de->name_len && de->inode) {
675 ext3fs_dirhash(de->name, de->name_len, &h);
676 map_tail--;
677 map_tail->hash = h.hash;
678 map_tail->offs = (u32) ((char *) de - base);
679 count++;
680 cond_resched();
681 }
682 /* XXX: do we need to check rec_len == 0 case? -Chris */
683 de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
684 }
685 return count;
686}
687
688static void dx_sort_map (struct dx_map_entry *map, unsigned count)
689{
690 struct dx_map_entry *p, *q, *top = map + count - 1;
691 int more;
692 /* Combsort until bubble sort doesn't suck */
693 while (count > 2)
694 {
695 count = count*10/13;
696 if (count - 9 < 2) /* 9, 10 -> 11 */
697 count = 11;
698 for (p = top, q = p - count; q >= map; p--, q--)
699 if (p->hash < q->hash)
700 swap(*p, *q);
701 }
702 /* Garden variety bubble sort */
703 do {
704 more = 0;
705 q = top;
706 while (q-- > map)
707 {
708 if (q[1].hash >= q[0].hash)
709 continue;
710 swap(*(q+1), *q);
711 more = 1;
712 }
713 } while(more);
714}
715
716static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
717{
718 struct dx_entry *entries = frame->entries;
719 struct dx_entry *old = frame->at, *new = old + 1;
720 int count = dx_get_count(entries);
721
722 assert(count < dx_get_limit(entries));
723 assert(old < entries + count);
724 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
725 dx_set_hash(new, hash);
726 dx_set_block(new, block);
727 dx_set_count(entries, count + 1);
728}
729#endif
730
731
732static void ext3_update_dx_flag(struct inode *inode)
733{
734 if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb,
735 EXT3_FEATURE_COMPAT_DIR_INDEX))
736 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL;
737}
738
739/*
740 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure.
741 *
742 * `len <= EXT3_NAME_LEN' is guaranteed by caller.
743 * `de != NULL' is guaranteed by caller.
744 */
745static inline int ext3_match (int len, const char * const name,
746 struct ext3_dir_entry_2 * de)
747{
748 if (len != de->name_len)
749 return 0;
750 if (!de->inode)
751 return 0;
752 return !memcmp(name, de->name, len);
753}
754
755/*
756 * Returns 0 if not found, -1 on failure, and 1 on success
757 */
758static inline int search_dirblock(struct buffer_head * bh,
759 struct inode *dir,
760 struct dentry *dentry,
761 unsigned long offset,
762 struct ext3_dir_entry_2 ** res_dir)
763{
764 struct ext3_dir_entry_2 * de;
765 char * dlimit;
766 int de_len;
767 const char *name = dentry->d_name.name;
768 int namelen = dentry->d_name.len;
769
770 de = (struct ext3_dir_entry_2 *) bh->b_data;
771 dlimit = bh->b_data + dir->i_sb->s_blocksize;
772 while ((char *) de < dlimit) {
773 /* this code is executed quadratically often */
774 /* do minimal checking `by hand' */
775
776 if ((char *) de + namelen <= dlimit &&
777 ext3_match (namelen, name, de)) {
778 /* found a match - just to be sure, do a full check */
779 if (!ext3_check_dir_entry("ext3_find_entry",
780 dir, de, bh, offset))
781 return -1;
782 *res_dir = de;
783 return 1;
784 }
785 /* prevent looping on a bad block */
786 de_len = le16_to_cpu(de->rec_len);
787 if (de_len <= 0)
788 return -1;
789 offset += de_len;
790 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len);
791 }
792 return 0;
793}
794
795
796/*
797 * ext3_find_entry()
798 *
799 * finds an entry in the specified directory with the wanted name. It
800 * returns the cache buffer in which the entry was found, and the entry
801 * itself (as a parameter - res_dir). It does NOT read the inode of the
802 * entry - you'll have to do that yourself if you want to.
803 *
804 * The returned buffer_head has ->b_count elevated. The caller is expected
805 * to brelse() it when appropriate.
806 */
807static struct buffer_head * ext3_find_entry (struct dentry *dentry,
808 struct ext3_dir_entry_2 ** res_dir)
809{
810 struct super_block * sb;
811 struct buffer_head * bh_use[NAMEI_RA_SIZE];
812 struct buffer_head * bh, *ret = NULL;
813 unsigned long start, block, b;
814 int ra_max = 0; /* Number of bh's in the readahead
815 buffer, bh_use[] */
816 int ra_ptr = 0; /* Current index into readahead
817 buffer */
818 int num = 0;
819 int nblocks, i, err;
820 struct inode *dir = dentry->d_parent->d_inode;
821 int namelen;
822 const u8 *name;
823 unsigned blocksize;
824
825 *res_dir = NULL;
826 sb = dir->i_sb;
827 blocksize = sb->s_blocksize;
828 namelen = dentry->d_name.len;
829 name = dentry->d_name.name;
830 if (namelen > EXT3_NAME_LEN)
831 return NULL;
832#ifdef CONFIG_EXT3_INDEX
833 if (is_dx(dir)) {
834 bh = ext3_dx_find_entry(dentry, res_dir, &err);
835 /*
836 * On success, or if the error was file not found,
837 * return. Otherwise, fall back to doing a search the
838 * old fashioned way.
839 */
840 if (bh || (err != ERR_BAD_DX_DIR))
841 return bh;
842 dxtrace(printk("ext3_find_entry: dx failed, falling back\n"));
843 }
844#endif
845 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
846 start = EXT3_I(dir)->i_dir_start_lookup;
847 if (start >= nblocks)
848 start = 0;
849 block = start;
850restart:
851 do {
852 /*
853 * We deal with the read-ahead logic here.
854 */
855 if (ra_ptr >= ra_max) {
856 /* Refill the readahead buffer */
857 ra_ptr = 0;
858 b = block;
859 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
860 /*
861 * Terminate if we reach the end of the
862 * directory and must wrap, or if our
863 * search has finished at this block.
864 */
865 if (b >= nblocks || (num && block == start)) {
866 bh_use[ra_max] = NULL;
867 break;
868 }
869 num++;
870 bh = ext3_getblk(NULL, dir, b++, 0, &err);
871 bh_use[ra_max] = bh;
872 if (bh)
873 ll_rw_block(READ, 1, &bh);
874 }
875 }
876 if ((bh = bh_use[ra_ptr++]) == NULL)
877 goto next;
878 wait_on_buffer(bh);
879 if (!buffer_uptodate(bh)) {
880 /* read error, skip block & hope for the best */
881 ext3_error(sb, __FUNCTION__, "reading directory #%lu "
882 "offset %lu", dir->i_ino, block);
883 brelse(bh);
884 goto next;
885 }
886 i = search_dirblock(bh, dir, dentry,
887 block << EXT3_BLOCK_SIZE_BITS(sb), res_dir);
888 if (i == 1) {
889 EXT3_I(dir)->i_dir_start_lookup = block;
890 ret = bh;
891 goto cleanup_and_exit;
892 } else {
893 brelse(bh);
894 if (i < 0)
895 goto cleanup_and_exit;
896 }
897 next:
898 if (++block >= nblocks)
899 block = 0;
900 } while (block != start);
901
902 /*
903 * If the directory has grown while we were searching, then
904 * search the last part of the directory before giving up.
905 */
906 block = nblocks;
907 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
908 if (block < nblocks) {
909 start = 0;
910 goto restart;
911 }
912
913cleanup_and_exit:
914 /* Clean up the read-ahead blocks */
915 for (; ra_ptr < ra_max; ra_ptr++)
916 brelse (bh_use[ra_ptr]);
917 return ret;
918}
919
920#ifdef CONFIG_EXT3_INDEX
921static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
922 struct ext3_dir_entry_2 **res_dir, int *err)
923{
924 struct super_block * sb;
925 struct dx_hash_info hinfo;
926 u32 hash;
927 struct dx_frame frames[2], *frame;
928 struct ext3_dir_entry_2 *de, *top;
929 struct buffer_head *bh;
930 unsigned long block;
931 int retval;
932 int namelen = dentry->d_name.len;
933 const u8 *name = dentry->d_name.name;
934 struct inode *dir = dentry->d_parent->d_inode;
935
936 sb = dir->i_sb;
Andreas Dilgeracfa1823d2005-06-23 00:09:45 -0700937 /* NFS may look up ".." - look at dx_root directory block */
938 if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
939 if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
940 return NULL;
941 } else {
942 frame = frames;
943 frame->bh = NULL; /* for dx_release() */
944 frame->at = (struct dx_entry *)frames; /* hack for zero entry*/
945 dx_set_block(frame->at, 0); /* dx_root block is 0 */
946 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 hash = hinfo.hash;
948 do {
949 block = dx_get_block(frame->at);
950 if (!(bh = ext3_bread (NULL,dir, block, 0, err)))
951 goto errout;
952 de = (struct ext3_dir_entry_2 *) bh->b_data;
953 top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize -
954 EXT3_DIR_REC_LEN(0));
955 for (; de < top; de = ext3_next_entry(de))
956 if (ext3_match (namelen, name, de)) {
957 if (!ext3_check_dir_entry("ext3_find_entry",
958 dir, de, bh,
959 (block<<EXT3_BLOCK_SIZE_BITS(sb))
960 +((char *)de - bh->b_data))) {
961 brelse (bh);
962 goto errout;
963 }
964 *res_dir = de;
965 dx_release (frames);
966 return bh;
967 }
968 brelse (bh);
969 /* Check to see if we should continue to search */
970 retval = ext3_htree_next_block(dir, hash, frame,
971 frames, NULL);
972 if (retval < 0) {
973 ext3_warning(sb, __FUNCTION__,
974 "error reading index page in directory #%lu",
975 dir->i_ino);
976 *err = retval;
977 goto errout;
978 }
979 } while (retval == 1);
980
981 *err = -ENOENT;
982errout:
983 dxtrace(printk("%s not found\n", name));
984 dx_release (frames);
985 return NULL;
986}
987#endif
988
989static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
990{
991 struct inode * inode;
992 struct ext3_dir_entry_2 * de;
993 struct buffer_head * bh;
994
995 if (dentry->d_name.len > EXT3_NAME_LEN)
996 return ERR_PTR(-ENAMETOOLONG);
997
998 bh = ext3_find_entry(dentry, &de);
999 inode = NULL;
1000 if (bh) {
1001 unsigned long ino = le32_to_cpu(de->inode);
1002 brelse (bh);
1003 inode = iget(dir->i_sb, ino);
1004
1005 if (!inode)
1006 return ERR_PTR(-EACCES);
1007 }
1008 if (inode)
1009 return d_splice_alias(inode, dentry);
1010 d_add(dentry, inode);
1011 return NULL;
1012}
1013
1014
1015struct dentry *ext3_get_parent(struct dentry *child)
1016{
1017 unsigned long ino;
1018 struct dentry *parent;
1019 struct inode *inode;
1020 struct dentry dotdot;
1021 struct ext3_dir_entry_2 * de;
1022 struct buffer_head *bh;
1023
1024 dotdot.d_name.name = "..";
1025 dotdot.d_name.len = 2;
1026 dotdot.d_parent = child; /* confusing, isn't it! */
1027
1028 bh = ext3_find_entry(&dotdot, &de);
1029 inode = NULL;
1030 if (!bh)
1031 return ERR_PTR(-ENOENT);
1032 ino = le32_to_cpu(de->inode);
1033 brelse(bh);
1034 inode = iget(child->d_inode->i_sb, ino);
1035
1036 if (!inode)
1037 return ERR_PTR(-EACCES);
1038
1039 parent = d_alloc_anon(inode);
1040 if (!parent) {
1041 iput(inode);
1042 parent = ERR_PTR(-ENOMEM);
1043 }
1044 return parent;
1045}
1046
1047#define S_SHIFT 12
1048static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = {
1049 [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE,
1050 [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR,
1051 [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV,
1052 [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV,
1053 [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO,
1054 [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK,
1055 [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK,
1056};
1057
1058static inline void ext3_set_de_type(struct super_block *sb,
1059 struct ext3_dir_entry_2 *de,
1060 umode_t mode) {
1061 if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE))
1062 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
1063}
1064
1065#ifdef CONFIG_EXT3_INDEX
1066static struct ext3_dir_entry_2 *
1067dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
1068{
1069 unsigned rec_len = 0;
1070
1071 while (count--) {
1072 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs);
1073 rec_len = EXT3_DIR_REC_LEN(de->name_len);
1074 memcpy (to, de, rec_len);
1075 ((struct ext3_dir_entry_2 *) to)->rec_len =
1076 cpu_to_le16(rec_len);
1077 de->inode = 0;
1078 map++;
1079 to += rec_len;
1080 }
1081 return (struct ext3_dir_entry_2 *) (to - rec_len);
1082}
1083
1084static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size)
1085{
1086 struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base;
1087 unsigned rec_len = 0;
1088
1089 prev = to = de;
1090 while ((char*)de < base + size) {
1091 next = (struct ext3_dir_entry_2 *) ((char *) de +
1092 le16_to_cpu(de->rec_len));
1093 if (de->inode && de->name_len) {
1094 rec_len = EXT3_DIR_REC_LEN(de->name_len);
1095 if (de > to)
1096 memmove(to, de, rec_len);
1097 to->rec_len = cpu_to_le16(rec_len);
1098 prev = to;
1099 to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len);
1100 }
1101 de = next;
1102 }
1103 return prev;
1104}
1105
1106static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
1107 struct buffer_head **bh,struct dx_frame *frame,
1108 struct dx_hash_info *hinfo, int *error)
1109{
1110 unsigned blocksize = dir->i_sb->s_blocksize;
1111 unsigned count, continued;
1112 struct buffer_head *bh2;
1113 u32 newblock;
1114 u32 hash2;
1115 struct dx_map_entry *map;
1116 char *data1 = (*bh)->b_data, *data2;
1117 unsigned split;
1118 struct ext3_dir_entry_2 *de = NULL, *de2;
1119 int err;
1120
1121 bh2 = ext3_append (handle, dir, &newblock, error);
1122 if (!(bh2)) {
1123 brelse(*bh);
1124 *bh = NULL;
1125 goto errout;
1126 }
1127
1128 BUFFER_TRACE(*bh, "get_write_access");
1129 err = ext3_journal_get_write_access(handle, *bh);
1130 if (err) {
1131 journal_error:
1132 brelse(*bh);
1133 brelse(bh2);
1134 *bh = NULL;
1135 ext3_std_error(dir->i_sb, err);
1136 goto errout;
1137 }
1138 BUFFER_TRACE(frame->bh, "get_write_access");
1139 err = ext3_journal_get_write_access(handle, frame->bh);
1140 if (err)
1141 goto journal_error;
1142
1143 data2 = bh2->b_data;
1144
1145 /* create map in the end of data2 block */
1146 map = (struct dx_map_entry *) (data2 + blocksize);
1147 count = dx_make_map ((struct ext3_dir_entry_2 *) data1,
1148 blocksize, hinfo, map);
1149 map -= count;
1150 split = count/2; // need to adjust to actual middle
1151 dx_sort_map (map, count);
1152 hash2 = map[split].hash;
1153 continued = hash2 == map[split - 1].hash;
1154 dxtrace(printk("Split block %i at %x, %i/%i\n",
1155 dx_get_block(frame->at), hash2, split, count-split));
1156
1157 /* Fancy dance to stay within two buffers */
1158 de2 = dx_move_dirents(data1, data2, map + split, count - split);
1159 de = dx_pack_dirents(data1,blocksize);
1160 de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
1161 de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2);
1162 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1));
1163 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1));
1164
1165 /* Which block gets the new entry? */
1166 if (hinfo->hash >= hash2)
1167 {
1168 swap(*bh, bh2);
1169 de = de2;
1170 }
1171 dx_insert_block (frame, hash2 + continued, newblock);
1172 err = ext3_journal_dirty_metadata (handle, bh2);
1173 if (err)
1174 goto journal_error;
1175 err = ext3_journal_dirty_metadata (handle, frame->bh);
1176 if (err)
1177 goto journal_error;
1178 brelse (bh2);
1179 dxtrace(dx_show_index ("frame", frame->entries));
1180errout:
1181 return de;
1182}
1183#endif
1184
1185
1186/*
1187 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1188 * it points to a directory entry which is guaranteed to be large
1189 * enough for new directory entry. If de is NULL, then
1190 * add_dirent_to_buf will attempt search the directory block for
1191 * space. It will return -ENOSPC if no space is available, and -EIO
1192 * and -EEXIST if directory entry already exists.
1193 *
1194 * NOTE! bh is NOT released in the case where ENOSPC is returned. In
1195 * all other cases bh is released.
1196 */
1197static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
1198 struct inode *inode, struct ext3_dir_entry_2 *de,
1199 struct buffer_head * bh)
1200{
1201 struct inode *dir = dentry->d_parent->d_inode;
1202 const char *name = dentry->d_name.name;
1203 int namelen = dentry->d_name.len;
1204 unsigned long offset = 0;
1205 unsigned short reclen;
1206 int nlen, rlen, err;
1207 char *top;
1208
1209 reclen = EXT3_DIR_REC_LEN(namelen);
1210 if (!de) {
1211 de = (struct ext3_dir_entry_2 *)bh->b_data;
1212 top = bh->b_data + dir->i_sb->s_blocksize - reclen;
1213 while ((char *) de <= top) {
1214 if (!ext3_check_dir_entry("ext3_add_entry", dir, de,
1215 bh, offset)) {
1216 brelse (bh);
1217 return -EIO;
1218 }
1219 if (ext3_match (namelen, name, de)) {
1220 brelse (bh);
1221 return -EEXIST;
1222 }
1223 nlen = EXT3_DIR_REC_LEN(de->name_len);
1224 rlen = le16_to_cpu(de->rec_len);
1225 if ((de->inode? rlen - nlen: rlen) >= reclen)
1226 break;
1227 de = (struct ext3_dir_entry_2 *)((char *)de + rlen);
1228 offset += rlen;
1229 }
1230 if ((char *) de > top)
1231 return -ENOSPC;
1232 }
1233 BUFFER_TRACE(bh, "get_write_access");
1234 err = ext3_journal_get_write_access(handle, bh);
1235 if (err) {
1236 ext3_std_error(dir->i_sb, err);
1237 brelse(bh);
1238 return err;
1239 }
1240
1241 /* By now the buffer is marked for journaling */
1242 nlen = EXT3_DIR_REC_LEN(de->name_len);
1243 rlen = le16_to_cpu(de->rec_len);
1244 if (de->inode) {
1245 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen);
1246 de1->rec_len = cpu_to_le16(rlen - nlen);
1247 de->rec_len = cpu_to_le16(nlen);
1248 de = de1;
1249 }
1250 de->file_type = EXT3_FT_UNKNOWN;
1251 if (inode) {
1252 de->inode = cpu_to_le32(inode->i_ino);
1253 ext3_set_de_type(dir->i_sb, de, inode->i_mode);
1254 } else
1255 de->inode = 0;
1256 de->name_len = namelen;
1257 memcpy (de->name, name, namelen);
1258 /*
1259 * XXX shouldn't update any times until successful
1260 * completion of syscall, but too many callers depend
1261 * on this.
1262 *
1263 * XXX similarly, too many callers depend on
1264 * ext3_new_inode() setting the times, but error
1265 * recovery deletes the inode, so the worst that can
1266 * happen is that the times are slightly out of date
1267 * and/or different from the directory change time.
1268 */
1269 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
1270 ext3_update_dx_flag(dir);
1271 dir->i_version++;
1272 ext3_mark_inode_dirty(handle, dir);
1273 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1274 err = ext3_journal_dirty_metadata(handle, bh);
1275 if (err)
1276 ext3_std_error(dir->i_sb, err);
1277 brelse(bh);
1278 return 0;
1279}
1280
1281#ifdef CONFIG_EXT3_INDEX
1282/*
1283 * This converts a one block unindexed directory to a 3 block indexed
1284 * directory, and adds the dentry to the indexed directory.
1285 */
1286static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1287 struct inode *inode, struct buffer_head *bh)
1288{
1289 struct inode *dir = dentry->d_parent->d_inode;
1290 const char *name = dentry->d_name.name;
1291 int namelen = dentry->d_name.len;
1292 struct buffer_head *bh2;
1293 struct dx_root *root;
1294 struct dx_frame frames[2], *frame;
1295 struct dx_entry *entries;
1296 struct ext3_dir_entry_2 *de, *de2;
1297 char *data1, *top;
1298 unsigned len;
1299 int retval;
1300 unsigned blocksize;
1301 struct dx_hash_info hinfo;
1302 u32 block;
1303 struct fake_dirent *fde;
1304
1305 blocksize = dir->i_sb->s_blocksize;
1306 dxtrace(printk("Creating index\n"));
1307 retval = ext3_journal_get_write_access(handle, bh);
1308 if (retval) {
1309 ext3_std_error(dir->i_sb, retval);
1310 brelse(bh);
1311 return retval;
1312 }
1313 root = (struct dx_root *) bh->b_data;
1314
1315 bh2 = ext3_append (handle, dir, &block, &retval);
1316 if (!(bh2)) {
1317 brelse(bh);
1318 return retval;
1319 }
1320 EXT3_I(dir)->i_flags |= EXT3_INDEX_FL;
1321 data1 = bh2->b_data;
1322
1323 /* The 0th block becomes the root, move the dirents out */
1324 fde = &root->dotdot;
1325 de = (struct ext3_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len));
1326 len = ((char *) root) + blocksize - (char *) de;
1327 memcpy (data1, de, len);
1328 de = (struct ext3_dir_entry_2 *) data1;
1329 top = data1 + len;
1330 while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top)
1331 de = de2;
1332 de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
1333 /* Initialize the root; the dot dirents already exist */
1334 de = (struct ext3_dir_entry_2 *) (&root->dotdot);
1335 de->rec_len = cpu_to_le16(blocksize - EXT3_DIR_REC_LEN(2));
1336 memset (&root->info, 0, sizeof(root->info));
1337 root->info.info_length = sizeof(root->info);
1338 root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
1339 entries = root->entries;
1340 dx_set_block (entries, 1);
1341 dx_set_count (entries, 1);
1342 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));
1343
1344 /* Initialize as for dx_probe */
1345 hinfo.hash_version = root->info.hash_version;
1346 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
1347 ext3fs_dirhash(name, namelen, &hinfo);
1348 frame = frames;
1349 frame->entries = entries;
1350 frame->at = entries;
1351 frame->bh = bh;
1352 bh = bh2;
1353 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
1354 dx_release (frames);
1355 if (!(de))
1356 return retval;
1357
1358 return add_dirent_to_buf(handle, dentry, inode, de, bh);
1359}
1360#endif
1361
1362/*
1363 * ext3_add_entry()
1364 *
1365 * adds a file entry to the specified directory, using the same
1366 * semantics as ext3_find_entry(). It returns NULL if it failed.
1367 *
1368 * NOTE!! The inode part of 'de' is left at 0 - which means you
1369 * may not sleep between calling this and putting something into
1370 * the entry, as someone else might have used it while you slept.
1371 */
1372static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
1373 struct inode *inode)
1374{
1375 struct inode *dir = dentry->d_parent->d_inode;
1376 unsigned long offset;
1377 struct buffer_head * bh;
1378 struct ext3_dir_entry_2 *de;
1379 struct super_block * sb;
1380 int retval;
1381#ifdef CONFIG_EXT3_INDEX
1382 int dx_fallback=0;
1383#endif
1384 unsigned blocksize;
1385 unsigned nlen, rlen;
1386 u32 block, blocks;
1387
1388 sb = dir->i_sb;
1389 blocksize = sb->s_blocksize;
1390 if (!dentry->d_name.len)
1391 return -EINVAL;
1392#ifdef CONFIG_EXT3_INDEX
1393 if (is_dx(dir)) {
1394 retval = ext3_dx_add_entry(handle, dentry, inode);
1395 if (!retval || (retval != ERR_BAD_DX_DIR))
1396 return retval;
1397 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL;
1398 dx_fallback++;
1399 ext3_mark_inode_dirty(handle, dir);
1400 }
1401#endif
1402 blocks = dir->i_size >> sb->s_blocksize_bits;
1403 for (block = 0, offset = 0; block < blocks; block++) {
1404 bh = ext3_bread(handle, dir, block, 0, &retval);
1405 if(!bh)
1406 return retval;
1407 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1408 if (retval != -ENOSPC)
1409 return retval;
1410
1411#ifdef CONFIG_EXT3_INDEX
1412 if (blocks == 1 && !dx_fallback &&
1413 EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
1414 return make_indexed_dir(handle, dentry, inode, bh);
1415#endif
1416 brelse(bh);
1417 }
1418 bh = ext3_append(handle, dir, &block, &retval);
1419 if (!bh)
1420 return retval;
1421 de = (struct ext3_dir_entry_2 *) bh->b_data;
1422 de->inode = 0;
1423 de->rec_len = cpu_to_le16(rlen = blocksize);
1424 nlen = 0;
1425 return add_dirent_to_buf(handle, dentry, inode, de, bh);
1426}
1427
1428#ifdef CONFIG_EXT3_INDEX
1429/*
1430 * Returns 0 for success, or a negative error value
1431 */
1432static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
1433 struct inode *inode)
1434{
1435 struct dx_frame frames[2], *frame;
1436 struct dx_entry *entries, *at;
1437 struct dx_hash_info hinfo;
1438 struct buffer_head * bh;
1439 struct inode *dir = dentry->d_parent->d_inode;
1440 struct super_block * sb = dir->i_sb;
1441 struct ext3_dir_entry_2 *de;
1442 int err;
1443
1444 frame = dx_probe(dentry, NULL, &hinfo, frames, &err);
1445 if (!frame)
1446 return err;
1447 entries = frame->entries;
1448 at = frame->at;
1449
1450 if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
1451 goto cleanup;
1452
1453 BUFFER_TRACE(bh, "get_write_access");
1454 err = ext3_journal_get_write_access(handle, bh);
1455 if (err)
1456 goto journal_error;
1457
1458 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1459 if (err != -ENOSPC) {
1460 bh = NULL;
1461 goto cleanup;
1462 }
1463
1464 /* Block full, should compress but for now just split */
1465 dxtrace(printk("using %u of %u node entries\n",
1466 dx_get_count(entries), dx_get_limit(entries)));
1467 /* Need to split index? */
1468 if (dx_get_count(entries) == dx_get_limit(entries)) {
1469 u32 newblock;
1470 unsigned icount = dx_get_count(entries);
1471 int levels = frame - frames;
1472 struct dx_entry *entries2;
1473 struct dx_node *node2;
1474 struct buffer_head *bh2;
1475
1476 if (levels && (dx_get_count(frames->entries) ==
1477 dx_get_limit(frames->entries))) {
1478 ext3_warning(sb, __FUNCTION__,
Glauber de Oliveira Costa9f406682006-01-08 01:03:22 -08001479 "Directory index full!");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001480 err = -ENOSPC;
1481 goto cleanup;
1482 }
1483 bh2 = ext3_append (handle, dir, &newblock, &err);
1484 if (!(bh2))
1485 goto cleanup;
1486 node2 = (struct dx_node *)(bh2->b_data);
1487 entries2 = node2->entries;
1488 node2->fake.rec_len = cpu_to_le16(sb->s_blocksize);
1489 node2->fake.inode = 0;
1490 BUFFER_TRACE(frame->bh, "get_write_access");
1491 err = ext3_journal_get_write_access(handle, frame->bh);
1492 if (err)
1493 goto journal_error;
1494 if (levels) {
1495 unsigned icount1 = icount/2, icount2 = icount - icount1;
1496 unsigned hash2 = dx_get_hash(entries + icount1);
1497 dxtrace(printk("Split index %i/%i\n", icount1, icount2));
1498
1499 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
1500 err = ext3_journal_get_write_access(handle,
1501 frames[0].bh);
1502 if (err)
1503 goto journal_error;
1504
1505 memcpy ((char *) entries2, (char *) (entries + icount1),
1506 icount2 * sizeof(struct dx_entry));
1507 dx_set_count (entries, icount1);
1508 dx_set_count (entries2, icount2);
1509 dx_set_limit (entries2, dx_node_limit(dir));
1510
1511 /* Which index block gets the new entry? */
1512 if (at - entries >= icount1) {
1513 frame->at = at = at - entries - icount1 + entries2;
1514 frame->entries = entries = entries2;
1515 swap(frame->bh, bh2);
1516 }
1517 dx_insert_block (frames + 0, hash2, newblock);
1518 dxtrace(dx_show_index ("node", frames[1].entries));
1519 dxtrace(dx_show_index ("node",
1520 ((struct dx_node *) bh2->b_data)->entries));
1521 err = ext3_journal_dirty_metadata(handle, bh2);
1522 if (err)
1523 goto journal_error;
1524 brelse (bh2);
1525 } else {
1526 dxtrace(printk("Creating second level index...\n"));
1527 memcpy((char *) entries2, (char *) entries,
1528 icount * sizeof(struct dx_entry));
1529 dx_set_limit(entries2, dx_node_limit(dir));
1530
1531 /* Set up root */
1532 dx_set_count(entries, 1);
1533 dx_set_block(entries + 0, newblock);
1534 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
1535
1536 /* Add new access path frame */
1537 frame = frames + 1;
1538 frame->at = at = at - entries + entries2;
1539 frame->entries = entries = entries2;
1540 frame->bh = bh2;
1541 err = ext3_journal_get_write_access(handle,
1542 frame->bh);
1543 if (err)
1544 goto journal_error;
1545 }
1546 ext3_journal_dirty_metadata(handle, frames[0].bh);
1547 }
1548 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
1549 if (!de)
1550 goto cleanup;
1551 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
1552 bh = NULL;
1553 goto cleanup;
1554
1555journal_error:
1556 ext3_std_error(dir->i_sb, err);
1557cleanup:
1558 if (bh)
1559 brelse(bh);
1560 dx_release(frames);
1561 return err;
1562}
1563#endif
1564
1565/*
1566 * ext3_delete_entry deletes a directory entry by merging it with the
1567 * previous entry
1568 */
1569static int ext3_delete_entry (handle_t *handle,
1570 struct inode * dir,
1571 struct ext3_dir_entry_2 * de_del,
1572 struct buffer_head * bh)
1573{
1574 struct ext3_dir_entry_2 * de, * pde;
1575 int i;
1576
1577 i = 0;
1578 pde = NULL;
1579 de = (struct ext3_dir_entry_2 *) bh->b_data;
1580 while (i < bh->b_size) {
1581 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i))
1582 return -EIO;
1583 if (de == de_del) {
1584 BUFFER_TRACE(bh, "get_write_access");
1585 ext3_journal_get_write_access(handle, bh);
1586 if (pde)
1587 pde->rec_len =
1588 cpu_to_le16(le16_to_cpu(pde->rec_len) +
1589 le16_to_cpu(de->rec_len));
1590 else
1591 de->inode = 0;
1592 dir->i_version++;
1593 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
1594 ext3_journal_dirty_metadata(handle, bh);
1595 return 0;
1596 }
1597 i += le16_to_cpu(de->rec_len);
1598 pde = de;
1599 de = (struct ext3_dir_entry_2 *)
1600 ((char *) de + le16_to_cpu(de->rec_len));
1601 }
1602 return -ENOENT;
1603}
1604
1605/*
1606 * ext3_mark_inode_dirty is somewhat expensive, so unlike ext2 we
1607 * do not perform it in these functions. We perform it at the call site,
1608 * if it is needed.
1609 */
1610static inline void ext3_inc_count(handle_t *handle, struct inode *inode)
1611{
1612 inode->i_nlink++;
1613}
1614
1615static inline void ext3_dec_count(handle_t *handle, struct inode *inode)
1616{
1617 inode->i_nlink--;
1618}
1619
1620static int ext3_add_nondir(handle_t *handle,
1621 struct dentry *dentry, struct inode *inode)
1622{
1623 int err = ext3_add_entry(handle, dentry, inode);
1624 if (!err) {
1625 ext3_mark_inode_dirty(handle, inode);
1626 d_instantiate(dentry, inode);
1627 return 0;
1628 }
1629 ext3_dec_count(handle, inode);
1630 iput(inode);
1631 return err;
1632}
1633
1634/*
1635 * By the time this is called, we already have created
1636 * the directory cache entry for the new file, but it
1637 * is so far negative - it has no inode.
1638 *
1639 * If the create succeeds, we fill in the inode information
1640 * with d_instantiate().
1641 */
1642static int ext3_create (struct inode * dir, struct dentry * dentry, int mode,
1643 struct nameidata *nd)
1644{
1645 handle_t *handle;
1646 struct inode * inode;
1647 int err, retries = 0;
1648
1649retry:
Jan Kara1f545872005-06-23 22:01:04 -07001650 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
Jan Kara1f545872005-06-23 22:01:04 -07001652 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653 if (IS_ERR(handle))
1654 return PTR_ERR(handle);
1655
1656 if (IS_DIRSYNC(dir))
1657 handle->h_sync = 1;
1658
1659 inode = ext3_new_inode (handle, dir, mode);
1660 err = PTR_ERR(inode);
1661 if (!IS_ERR(inode)) {
1662 inode->i_op = &ext3_file_inode_operations;
1663 inode->i_fop = &ext3_file_operations;
1664 ext3_set_aops(inode);
1665 err = ext3_add_nondir(handle, dentry, inode);
1666 }
1667 ext3_journal_stop(handle);
1668 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1669 goto retry;
1670 return err;
1671}
1672
1673static int ext3_mknod (struct inode * dir, struct dentry *dentry,
1674 int mode, dev_t rdev)
1675{
1676 handle_t *handle;
1677 struct inode *inode;
1678 int err, retries = 0;
1679
1680 if (!new_valid_dev(rdev))
1681 return -EINVAL;
1682
1683retry:
Jan Kara1f545872005-06-23 22:01:04 -07001684 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
Jan Kara1f545872005-06-23 22:01:04 -07001686 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001687 if (IS_ERR(handle))
1688 return PTR_ERR(handle);
1689
1690 if (IS_DIRSYNC(dir))
1691 handle->h_sync = 1;
1692
1693 inode = ext3_new_inode (handle, dir, mode);
1694 err = PTR_ERR(inode);
1695 if (!IS_ERR(inode)) {
1696 init_special_inode(inode, inode->i_mode, rdev);
1697#ifdef CONFIG_EXT3_FS_XATTR
1698 inode->i_op = &ext3_special_inode_operations;
1699#endif
1700 err = ext3_add_nondir(handle, dentry, inode);
1701 }
1702 ext3_journal_stop(handle);
1703 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1704 goto retry;
1705 return err;
1706}
1707
1708static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode)
1709{
1710 handle_t *handle;
1711 struct inode * inode;
1712 struct buffer_head * dir_block;
1713 struct ext3_dir_entry_2 * de;
1714 int err, retries = 0;
1715
1716 if (dir->i_nlink >= EXT3_LINK_MAX)
1717 return -EMLINK;
1718
1719retry:
Jan Kara1f545872005-06-23 22:01:04 -07001720 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07001721 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
Jan Kara1f545872005-06-23 22:01:04 -07001722 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001723 if (IS_ERR(handle))
1724 return PTR_ERR(handle);
1725
1726 if (IS_DIRSYNC(dir))
1727 handle->h_sync = 1;
1728
1729 inode = ext3_new_inode (handle, dir, S_IFDIR | mode);
1730 err = PTR_ERR(inode);
1731 if (IS_ERR(inode))
1732 goto out_stop;
1733
1734 inode->i_op = &ext3_dir_inode_operations;
1735 inode->i_fop = &ext3_dir_operations;
1736 inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1737 dir_block = ext3_bread (handle, inode, 0, 1, &err);
1738 if (!dir_block) {
1739 inode->i_nlink--; /* is this nlink == 0? */
1740 ext3_mark_inode_dirty(handle, inode);
1741 iput (inode);
1742 goto out_stop;
1743 }
1744 BUFFER_TRACE(dir_block, "get_write_access");
1745 ext3_journal_get_write_access(handle, dir_block);
1746 de = (struct ext3_dir_entry_2 *) dir_block->b_data;
1747 de->inode = cpu_to_le32(inode->i_ino);
1748 de->name_len = 1;
1749 de->rec_len = cpu_to_le16(EXT3_DIR_REC_LEN(de->name_len));
1750 strcpy (de->name, ".");
1751 ext3_set_de_type(dir->i_sb, de, S_IFDIR);
1752 de = (struct ext3_dir_entry_2 *)
1753 ((char *) de + le16_to_cpu(de->rec_len));
1754 de->inode = cpu_to_le32(dir->i_ino);
1755 de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3_DIR_REC_LEN(1));
1756 de->name_len = 2;
1757 strcpy (de->name, "..");
1758 ext3_set_de_type(dir->i_sb, de, S_IFDIR);
1759 inode->i_nlink = 2;
1760 BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata");
1761 ext3_journal_dirty_metadata(handle, dir_block);
1762 brelse (dir_block);
1763 ext3_mark_inode_dirty(handle, inode);
1764 err = ext3_add_entry (handle, dentry, inode);
1765 if (err) {
1766 inode->i_nlink = 0;
1767 ext3_mark_inode_dirty(handle, inode);
1768 iput (inode);
1769 goto out_stop;
1770 }
1771 dir->i_nlink++;
1772 ext3_update_dx_flag(dir);
1773 ext3_mark_inode_dirty(handle, dir);
1774 d_instantiate(dentry, inode);
1775out_stop:
1776 ext3_journal_stop(handle);
1777 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
1778 goto retry;
1779 return err;
1780}
1781
1782/*
1783 * routine to check that the specified directory is empty (for rmdir)
1784 */
1785static int empty_dir (struct inode * inode)
1786{
1787 unsigned long offset;
1788 struct buffer_head * bh;
1789 struct ext3_dir_entry_2 * de, * de1;
1790 struct super_block * sb;
1791 int err = 0;
1792
1793 sb = inode->i_sb;
1794 if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) ||
1795 !(bh = ext3_bread (NULL, inode, 0, 0, &err))) {
1796 if (err)
1797 ext3_error(inode->i_sb, __FUNCTION__,
1798 "error %d reading directory #%lu offset 0",
1799 err, inode->i_ino);
1800 else
1801 ext3_warning(inode->i_sb, __FUNCTION__,
1802 "bad directory (dir #%lu) - no data block",
1803 inode->i_ino);
1804 return 1;
1805 }
1806 de = (struct ext3_dir_entry_2 *) bh->b_data;
1807 de1 = (struct ext3_dir_entry_2 *)
1808 ((char *) de + le16_to_cpu(de->rec_len));
1809 if (le32_to_cpu(de->inode) != inode->i_ino ||
1810 !le32_to_cpu(de1->inode) ||
1811 strcmp (".", de->name) ||
1812 strcmp ("..", de1->name)) {
1813 ext3_warning (inode->i_sb, "empty_dir",
1814 "bad directory (dir #%lu) - no `.' or `..'",
1815 inode->i_ino);
1816 brelse (bh);
1817 return 1;
1818 }
1819 offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
1820 de = (struct ext3_dir_entry_2 *)
1821 ((char *) de1 + le16_to_cpu(de1->rec_len));
1822 while (offset < inode->i_size ) {
1823 if (!bh ||
1824 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
1825 err = 0;
1826 brelse (bh);
1827 bh = ext3_bread (NULL, inode,
1828 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err);
1829 if (!bh) {
1830 if (err)
1831 ext3_error(sb, __FUNCTION__,
1832 "error %d reading directory"
1833 " #%lu offset %lu",
1834 err, inode->i_ino, offset);
1835 offset += sb->s_blocksize;
1836 continue;
1837 }
1838 de = (struct ext3_dir_entry_2 *) bh->b_data;
1839 }
1840 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) {
1841 de = (struct ext3_dir_entry_2 *)(bh->b_data +
1842 sb->s_blocksize);
1843 offset = (offset | (sb->s_blocksize - 1)) + 1;
1844 continue;
1845 }
1846 if (le32_to_cpu(de->inode)) {
1847 brelse (bh);
1848 return 0;
1849 }
1850 offset += le16_to_cpu(de->rec_len);
1851 de = (struct ext3_dir_entry_2 *)
1852 ((char *) de + le16_to_cpu(de->rec_len));
1853 }
1854 brelse (bh);
1855 return 1;
1856}
1857
1858/* ext3_orphan_add() links an unlinked or truncated inode into a list of
1859 * such inodes, starting at the superblock, in case we crash before the
1860 * file is closed/deleted, or in case the inode truncate spans multiple
1861 * transactions and the last transaction is not recovered after a crash.
1862 *
1863 * At filesystem recovery time, we walk this list deleting unlinked
1864 * inodes and truncating linked inodes in ext3_orphan_cleanup().
1865 */
1866int ext3_orphan_add(handle_t *handle, struct inode *inode)
1867{
1868 struct super_block *sb = inode->i_sb;
1869 struct ext3_iloc iloc;
1870 int err = 0, rc;
1871
1872 lock_super(sb);
1873 if (!list_empty(&EXT3_I(inode)->i_orphan))
1874 goto out_unlock;
1875
1876 /* Orphan handling is only valid for files with data blocks
1877 * being truncated, or files being unlinked. */
1878
1879 /* @@@ FIXME: Observation from aviro:
1880 * I think I can trigger J_ASSERT in ext3_orphan_add(). We block
1881 * here (on lock_super()), so race with ext3_link() which might bump
1882 * ->i_nlink. For, say it, character device. Not a regular file,
1883 * not a directory, not a symlink and ->i_nlink > 0.
1884 */
1885 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1886 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
1887
1888 BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access");
1889 err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
1890 if (err)
1891 goto out_unlock;
1892
1893 err = ext3_reserve_inode_write(handle, inode, &iloc);
1894 if (err)
1895 goto out_unlock;
1896
1897 /* Insert this inode at the head of the on-disk orphan list... */
1898 NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan);
1899 EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
1900 err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
1901 rc = ext3_mark_iloc_dirty(handle, inode, &iloc);
1902 if (!err)
1903 err = rc;
1904
1905 /* Only add to the head of the in-memory list if all the
1906 * previous operations succeeded. If the orphan_add is going to
1907 * fail (possibly taking the journal offline), we can't risk
1908 * leaving the inode on the orphan list: stray orphan-list
1909 * entries can cause panics at unmount time.
1910 *
1911 * This is safe: on error we're going to ignore the orphan list
1912 * anyway on the next recovery. */
1913 if (!err)
1914 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan);
1915
1916 jbd_debug(4, "superblock will point to %ld\n", inode->i_ino);
1917 jbd_debug(4, "orphan inode %ld will point to %d\n",
1918 inode->i_ino, NEXT_ORPHAN(inode));
1919out_unlock:
1920 unlock_super(sb);
1921 ext3_std_error(inode->i_sb, err);
1922 return err;
1923}
1924
1925/*
1926 * ext3_orphan_del() removes an unlinked or truncated inode from the list
1927 * of such inodes stored on disk, because it is finally being cleaned up.
1928 */
1929int ext3_orphan_del(handle_t *handle, struct inode *inode)
1930{
1931 struct list_head *prev;
1932 struct ext3_inode_info *ei = EXT3_I(inode);
1933 struct ext3_sb_info *sbi;
1934 unsigned long ino_next;
1935 struct ext3_iloc iloc;
1936 int err = 0;
1937
1938 lock_super(inode->i_sb);
1939 if (list_empty(&ei->i_orphan)) {
1940 unlock_super(inode->i_sb);
1941 return 0;
1942 }
1943
1944 ino_next = NEXT_ORPHAN(inode);
1945 prev = ei->i_orphan.prev;
1946 sbi = EXT3_SB(inode->i_sb);
1947
1948 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
1949
1950 list_del_init(&ei->i_orphan);
1951
1952 /* If we're on an error path, we may not have a valid
1953 * transaction handle with which to update the orphan list on
1954 * disk, but we still need to remove the inode from the linked
1955 * list in memory. */
1956 if (!handle)
1957 goto out;
1958
1959 err = ext3_reserve_inode_write(handle, inode, &iloc);
1960 if (err)
1961 goto out_err;
1962
1963 if (prev == &sbi->s_orphan) {
1964 jbd_debug(4, "superblock will point to %lu\n", ino_next);
1965 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
1966 err = ext3_journal_get_write_access(handle, sbi->s_sbh);
1967 if (err)
1968 goto out_brelse;
1969 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
1970 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
1971 } else {
1972 struct ext3_iloc iloc2;
1973 struct inode *i_prev =
1974 &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode;
1975
1976 jbd_debug(4, "orphan inode %lu will point to %lu\n",
1977 i_prev->i_ino, ino_next);
1978 err = ext3_reserve_inode_write(handle, i_prev, &iloc2);
1979 if (err)
1980 goto out_brelse;
1981 NEXT_ORPHAN(i_prev) = ino_next;
1982 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2);
1983 }
1984 if (err)
1985 goto out_brelse;
1986 NEXT_ORPHAN(inode) = 0;
1987 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
1988
1989out_err:
1990 ext3_std_error(inode->i_sb, err);
1991out:
1992 unlock_super(inode->i_sb);
1993 return err;
1994
1995out_brelse:
1996 brelse(iloc.bh);
1997 goto out_err;
1998}
1999
2000static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
2001{
2002 int retval;
2003 struct inode * inode;
2004 struct buffer_head * bh;
2005 struct ext3_dir_entry_2 * de;
2006 handle_t *handle;
2007
2008 /* Initialize quotas before so that eventual writes go in
2009 * separate transaction */
2010 DQUOT_INIT(dentry->d_inode);
Jan Kara1f545872005-06-23 22:01:04 -07002011 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002012 if (IS_ERR(handle))
2013 return PTR_ERR(handle);
2014
2015 retval = -ENOENT;
2016 bh = ext3_find_entry (dentry, &de);
2017 if (!bh)
2018 goto end_rmdir;
2019
2020 if (IS_DIRSYNC(dir))
2021 handle->h_sync = 1;
2022
2023 inode = dentry->d_inode;
2024
2025 retval = -EIO;
2026 if (le32_to_cpu(de->inode) != inode->i_ino)
2027 goto end_rmdir;
2028
2029 retval = -ENOTEMPTY;
2030 if (!empty_dir (inode))
2031 goto end_rmdir;
2032
2033 retval = ext3_delete_entry(handle, dir, de, bh);
2034 if (retval)
2035 goto end_rmdir;
2036 if (inode->i_nlink != 2)
2037 ext3_warning (inode->i_sb, "ext3_rmdir",
2038 "empty directory has nlink!=2 (%d)",
2039 inode->i_nlink);
2040 inode->i_version++;
2041 inode->i_nlink = 0;
2042 /* There's no need to set i_disksize: the fact that i_nlink is
2043 * zero will ensure that the right thing happens during any
2044 * recovery. */
2045 inode->i_size = 0;
2046 ext3_orphan_add(handle, inode);
2047 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
2048 ext3_mark_inode_dirty(handle, inode);
2049 dir->i_nlink--;
2050 ext3_update_dx_flag(dir);
2051 ext3_mark_inode_dirty(handle, dir);
2052
2053end_rmdir:
2054 ext3_journal_stop(handle);
2055 brelse (bh);
2056 return retval;
2057}
2058
2059static int ext3_unlink(struct inode * dir, struct dentry *dentry)
2060{
2061 int retval;
2062 struct inode * inode;
2063 struct buffer_head * bh;
2064 struct ext3_dir_entry_2 * de;
2065 handle_t *handle;
2066
2067 /* Initialize quotas before so that eventual writes go
2068 * in separate transaction */
2069 DQUOT_INIT(dentry->d_inode);
Jan Kara1f545872005-06-23 22:01:04 -07002070 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002071 if (IS_ERR(handle))
2072 return PTR_ERR(handle);
2073
2074 if (IS_DIRSYNC(dir))
2075 handle->h_sync = 1;
2076
2077 retval = -ENOENT;
2078 bh = ext3_find_entry (dentry, &de);
2079 if (!bh)
2080 goto end_unlink;
2081
2082 inode = dentry->d_inode;
2083
2084 retval = -EIO;
2085 if (le32_to_cpu(de->inode) != inode->i_ino)
2086 goto end_unlink;
2087
2088 if (!inode->i_nlink) {
2089 ext3_warning (inode->i_sb, "ext3_unlink",
2090 "Deleting nonexistent file (%lu), %d",
2091 inode->i_ino, inode->i_nlink);
2092 inode->i_nlink = 1;
2093 }
2094 retval = ext3_delete_entry(handle, dir, de, bh);
2095 if (retval)
2096 goto end_unlink;
2097 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
2098 ext3_update_dx_flag(dir);
2099 ext3_mark_inode_dirty(handle, dir);
2100 inode->i_nlink--;
2101 if (!inode->i_nlink)
2102 ext3_orphan_add(handle, inode);
2103 inode->i_ctime = dir->i_ctime;
2104 ext3_mark_inode_dirty(handle, inode);
2105 retval = 0;
2106
2107end_unlink:
2108 ext3_journal_stop(handle);
2109 brelse (bh);
2110 return retval;
2111}
2112
2113static int ext3_symlink (struct inode * dir,
2114 struct dentry *dentry, const char * symname)
2115{
2116 handle_t *handle;
2117 struct inode * inode;
2118 int l, err, retries = 0;
2119
2120 l = strlen(symname)+1;
2121 if (l > dir->i_sb->s_blocksize)
2122 return -ENAMETOOLONG;
2123
2124retry:
Jan Kara1f545872005-06-23 22:01:04 -07002125 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07002126 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 +
Jan Kara1f545872005-06-23 22:01:04 -07002127 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002128 if (IS_ERR(handle))
2129 return PTR_ERR(handle);
2130
2131 if (IS_DIRSYNC(dir))
2132 handle->h_sync = 1;
2133
2134 inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
2135 err = PTR_ERR(inode);
2136 if (IS_ERR(inode))
2137 goto out_stop;
2138
2139 if (l > sizeof (EXT3_I(inode)->i_data)) {
2140 inode->i_op = &ext3_symlink_inode_operations;
2141 ext3_set_aops(inode);
2142 /*
2143 * page_symlink() calls into ext3_prepare/commit_write.
2144 * We have a transaction open. All is sweetness. It also sets
2145 * i_size in generic_commit_write().
2146 */
2147 err = page_symlink(inode, symname, l);
2148 if (err) {
2149 ext3_dec_count(handle, inode);
2150 ext3_mark_inode_dirty(handle, inode);
2151 iput (inode);
2152 goto out_stop;
2153 }
2154 } else {
2155 inode->i_op = &ext3_fast_symlink_inode_operations;
2156 memcpy((char*)&EXT3_I(inode)->i_data,symname,l);
2157 inode->i_size = l-1;
2158 }
2159 EXT3_I(inode)->i_disksize = inode->i_size;
2160 err = ext3_add_nondir(handle, dentry, inode);
2161out_stop:
2162 ext3_journal_stop(handle);
2163 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
2164 goto retry;
2165 return err;
2166}
2167
2168static int ext3_link (struct dentry * old_dentry,
2169 struct inode * dir, struct dentry *dentry)
2170{
2171 handle_t *handle;
2172 struct inode *inode = old_dentry->d_inode;
2173 int err, retries = 0;
2174
2175 if (inode->i_nlink >= EXT3_LINK_MAX)
2176 return -EMLINK;
2177
2178retry:
Jan Kara1f545872005-06-23 22:01:04 -07002179 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07002180 EXT3_INDEX_EXTRA_TRANS_BLOCKS);
2181 if (IS_ERR(handle))
2182 return PTR_ERR(handle);
2183
2184 if (IS_DIRSYNC(dir))
2185 handle->h_sync = 1;
2186
2187 inode->i_ctime = CURRENT_TIME_SEC;
2188 ext3_inc_count(handle, inode);
2189 atomic_inc(&inode->i_count);
2190
2191 err = ext3_add_nondir(handle, dentry, inode);
2192 ext3_journal_stop(handle);
2193 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
2194 goto retry;
2195 return err;
2196}
2197
2198#define PARENT_INO(buffer) \
2199 ((struct ext3_dir_entry_2 *) ((char *) buffer + \
2200 le16_to_cpu(((struct ext3_dir_entry_2 *) buffer)->rec_len)))->inode
2201
2202/*
2203 * Anybody can rename anything with this: the permission checks are left to the
2204 * higher-level routines.
2205 */
2206static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
2207 struct inode * new_dir,struct dentry *new_dentry)
2208{
2209 handle_t *handle;
2210 struct inode * old_inode, * new_inode;
2211 struct buffer_head * old_bh, * new_bh, * dir_bh;
2212 struct ext3_dir_entry_2 * old_de, * new_de;
2213 int retval;
2214
2215 old_bh = new_bh = dir_bh = NULL;
2216
2217 /* Initialize quotas before so that eventual writes go
2218 * in separate transaction */
2219 if (new_dentry->d_inode)
2220 DQUOT_INIT(new_dentry->d_inode);
Jan Kara1f545872005-06-23 22:01:04 -07002221 handle = ext3_journal_start(old_dir, 2 *
2222 EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) +
Linus Torvalds1da177e2005-04-16 15:20:36 -07002223 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2);
2224 if (IS_ERR(handle))
2225 return PTR_ERR(handle);
2226
2227 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
2228 handle->h_sync = 1;
2229
2230 old_bh = ext3_find_entry (old_dentry, &old_de);
2231 /*
2232 * Check for inode number is _not_ due to possible IO errors.
2233 * We might rmdir the source, keep it as pwd of some process
2234 * and merrily kill the link to whatever was created under the
2235 * same name. Goodbye sticky bit ;-<
2236 */
2237 old_inode = old_dentry->d_inode;
2238 retval = -ENOENT;
2239 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
2240 goto end_rename;
2241
2242 new_inode = new_dentry->d_inode;
2243 new_bh = ext3_find_entry (new_dentry, &new_de);
2244 if (new_bh) {
2245 if (!new_inode) {
2246 brelse (new_bh);
2247 new_bh = NULL;
2248 }
2249 }
2250 if (S_ISDIR(old_inode->i_mode)) {
2251 if (new_inode) {
2252 retval = -ENOTEMPTY;
2253 if (!empty_dir (new_inode))
2254 goto end_rename;
2255 }
2256 retval = -EIO;
2257 dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval);
2258 if (!dir_bh)
2259 goto end_rename;
2260 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
2261 goto end_rename;
2262 retval = -EMLINK;
2263 if (!new_inode && new_dir!=old_dir &&
2264 new_dir->i_nlink >= EXT3_LINK_MAX)
2265 goto end_rename;
2266 }
2267 if (!new_bh) {
2268 retval = ext3_add_entry (handle, new_dentry, old_inode);
2269 if (retval)
2270 goto end_rename;
2271 } else {
2272 BUFFER_TRACE(new_bh, "get write access");
2273 ext3_journal_get_write_access(handle, new_bh);
2274 new_de->inode = cpu_to_le32(old_inode->i_ino);
2275 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
2276 EXT3_FEATURE_INCOMPAT_FILETYPE))
2277 new_de->file_type = old_de->file_type;
2278 new_dir->i_version++;
2279 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata");
2280 ext3_journal_dirty_metadata(handle, new_bh);
2281 brelse(new_bh);
2282 new_bh = NULL;
2283 }
2284
2285 /*
2286 * Like most other Unix systems, set the ctime for inodes on a
2287 * rename.
2288 */
2289 old_inode->i_ctime = CURRENT_TIME_SEC;
2290 ext3_mark_inode_dirty(handle, old_inode);
2291
2292 /*
2293 * ok, that's it
2294 */
2295 if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
2296 old_de->name_len != old_dentry->d_name.len ||
2297 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
2298 (retval = ext3_delete_entry(handle, old_dir,
2299 old_de, old_bh)) == -ENOENT) {
2300 /* old_de could have moved from under us during htree split, so
2301 * make sure that we are deleting the right entry. We might
2302 * also be pointing to a stale entry in the unused part of
2303 * old_bh so just checking inum and the name isn't enough. */
2304 struct buffer_head *old_bh2;
2305 struct ext3_dir_entry_2 *old_de2;
2306
2307 old_bh2 = ext3_find_entry(old_dentry, &old_de2);
2308 if (old_bh2) {
2309 retval = ext3_delete_entry(handle, old_dir,
2310 old_de2, old_bh2);
2311 brelse(old_bh2);
2312 }
2313 }
2314 if (retval) {
2315 ext3_warning(old_dir->i_sb, "ext3_rename",
2316 "Deleting old file (%lu), %d, error=%d",
2317 old_dir->i_ino, old_dir->i_nlink, retval);
2318 }
2319
2320 if (new_inode) {
2321 new_inode->i_nlink--;
2322 new_inode->i_ctime = CURRENT_TIME_SEC;
2323 }
2324 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
2325 ext3_update_dx_flag(old_dir);
2326 if (dir_bh) {
2327 BUFFER_TRACE(dir_bh, "get_write_access");
2328 ext3_journal_get_write_access(handle, dir_bh);
2329 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
2330 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata");
2331 ext3_journal_dirty_metadata(handle, dir_bh);
2332 old_dir->i_nlink--;
2333 if (new_inode) {
2334 new_inode->i_nlink--;
2335 } else {
2336 new_dir->i_nlink++;
2337 ext3_update_dx_flag(new_dir);
2338 ext3_mark_inode_dirty(handle, new_dir);
2339 }
2340 }
2341 ext3_mark_inode_dirty(handle, old_dir);
2342 if (new_inode) {
2343 ext3_mark_inode_dirty(handle, new_inode);
2344 if (!new_inode->i_nlink)
2345 ext3_orphan_add(handle, new_inode);
2346 }
2347 retval = 0;
2348
2349end_rename:
2350 brelse (dir_bh);
2351 brelse (old_bh);
2352 brelse (new_bh);
2353 ext3_journal_stop(handle);
2354 return retval;
2355}
2356
2357/*
2358 * directories can handle most operations...
2359 */
2360struct inode_operations ext3_dir_inode_operations = {
2361 .create = ext3_create,
2362 .lookup = ext3_lookup,
2363 .link = ext3_link,
2364 .unlink = ext3_unlink,
2365 .symlink = ext3_symlink,
2366 .mkdir = ext3_mkdir,
2367 .rmdir = ext3_rmdir,
2368 .mknod = ext3_mknod,
2369 .rename = ext3_rename,
2370 .setattr = ext3_setattr,
2371#ifdef CONFIG_EXT3_FS_XATTR
2372 .setxattr = generic_setxattr,
2373 .getxattr = generic_getxattr,
2374 .listxattr = ext3_listxattr,
2375 .removexattr = generic_removexattr,
2376#endif
2377 .permission = ext3_permission,
2378};
2379
2380struct inode_operations ext3_special_inode_operations = {
2381 .setattr = ext3_setattr,
2382#ifdef CONFIG_EXT3_FS_XATTR
2383 .setxattr = generic_setxattr,
2384 .getxattr = generic_getxattr,
2385 .listxattr = ext3_listxattr,
2386 .removexattr = generic_removexattr,
2387#endif
2388 .permission = ext3_permission,
2389};