blob: da224974af7861efeab66cdd0de475e0679f9432 [file] [log] [blame]
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001/*
Mingming Cao617ba132006-10-11 01:20:53 -07002 * linux/fs/ext4/namei.c
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003 *
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>
Mingming Caodab291a2006-10-11 01:21:01 -070029#include <linux/jbd2.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070030#include <linux/time.h>
Mingming Cao617ba132006-10-11 01:20:53 -070031#include <linux/ext4_fs.h>
Mingming Caodab291a2006-10-11 01:21:01 -070032#include <linux/ext4_jbd2.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070033#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/bio.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070039
40#include "namei.h"
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
Dave Kleikamp8c55e202007-05-24 13:04:54 -040049#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070050#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
51
Mingming Cao617ba132006-10-11 01:20:53 -070052static struct buffer_head *ext4_append(handle_t *handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -070053 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
Mingming Cao617ba132006-10-11 01:20:53 -070060 if ((bh = ext4_bread(handle, inode, *block, 1, err))) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -070061 inode->i_size += inode->i_sb->s_blocksize;
Mingming Cao617ba132006-10-11 01:20:53 -070062 EXT4_I(inode)->i_disksize = inode->i_size;
63 ext4_journal_get_write_access(handle,bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -070064 }
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
Mingming Cao617ba132006-10-11 01:20:53 -0700146#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700147static 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);
Mingming Cao617ba132006-10-11 01:20:53 -0700163static int dx_make_map (struct ext4_dir_entry_2 *de, int size,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700164 struct dx_hash_info *hinfo, struct dx_map_entry map[]);
165static void dx_sort_map(struct dx_map_entry *map, unsigned count);
Mingming Cao617ba132006-10-11 01:20:53 -0700166static struct ext4_dir_entry_2 *dx_move_dirents (char *from, char *to,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700167 struct dx_map_entry *offsets, int count);
Mingming Cao617ba132006-10-11 01:20:53 -0700168static struct ext4_dir_entry_2* dx_pack_dirents (char *base, int size);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700169static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block);
Mingming Cao617ba132006-10-11 01:20:53 -0700170static int ext4_htree_next_block(struct inode *dir, __u32 hash,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700171 struct dx_frame *frame,
172 struct dx_frame *frames,
173 __u32 *start_hash);
Mingming Cao617ba132006-10-11 01:20:53 -0700174static struct buffer_head * ext4_dx_find_entry(struct dentry *dentry,
175 struct ext4_dir_entry_2 **res_dir, int *err);
176static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700177 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{
Mingming Cao617ba132006-10-11 01:20:53 -0700226 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
227 EXT4_DIR_REC_LEN(2) - infosize;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700228 return 0? 20: entry_space / sizeof(struct dx_entry);
229}
230
231static inline unsigned dx_node_limit (struct inode *dir)
232{
Mingming Cao617ba132006-10-11 01:20:53 -0700233 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700234 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{
Andrew Morton63f57932006-10-11 01:21:24 -0700243 int i, n = dx_get_count (entries);
Dave Kleikamp8c55e202007-05-24 13:04:54 -0400244 printk("%s index ", label);
Andrew Morton63f57932006-10-11 01:21:24 -0700245 for (i = 0; i < n; i++) {
246 printk("%x->%u ", i? dx_get_hash(entries + i) :
247 0, dx_get_block(entries + i));
248 }
249 printk("\n");
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700250}
251
252struct stats
253{
254 unsigned names;
255 unsigned space;
256 unsigned bcount;
257};
258
Mingming Cao617ba132006-10-11 01:20:53 -0700259static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700260 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++);
Mingming Cao617ba132006-10-11 01:20:53 -0700276 ext4fs_dirhash(de->name, de->name_len, &h);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700277 printk(":%x.%u ", h.hash,
278 ((char *) de - base));
279 }
Mingming Cao617ba132006-10-11 01:20:53 -0700280 space += EXT4_DIR_REC_LEN(de->name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700281 names++;
282 }
Mingming Cao617ba132006-10-11 01:20:53 -0700283 de = (struct ext4_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700284 }
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);
Mingming Cao617ba132006-10-11 01:20:53 -0700304 if (!(bh = ext4_bread (NULL,dir, block, 0,&err))) continue;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700305 stats = levels?
306 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
Mingming Cao617ba132006-10-11 01:20:53 -0700307 dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700308 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;
Mingming Cao617ba132006-10-11 01:20:53 -0700343 if (!(bh = ext4_bread (NULL,dir, 0, 0, err)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700344 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) {
Mingming Cao617ba132006-10-11 01:20:53 -0700349 ext4_warning(dir->i_sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700350 "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;
Mingming Cao617ba132006-10-11 01:20:53 -0700357 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700358 if (dentry)
Mingming Cao617ba132006-10-11 01:20:53 -0700359 ext4fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700360 hash = hinfo->hash;
361
362 if (root->info.unused_flags & 1) {
Mingming Cao617ba132006-10-11 01:20:53 -0700363 ext4_warning(dir->i_sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700364 "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) {
Mingming Cao617ba132006-10-11 01:20:53 -0700372 ext4_warning(dir->i_sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700373 "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;
Mingming Cao617ba132006-10-11 01:20:53 -0700423 if (!(bh = ext4_bread (NULL,dir, dx_get_block(at), 0, err)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700424 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 */
Mingming Cao617ba132006-10-11 01:20:53 -0700465static int ext4_htree_next_block(struct inode *dir, __u32 hash,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700466 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--) {
Mingming Cao617ba132006-10-11 01:20:53 -0700511 if (!(bh = ext4_bread(NULL, dir, dx_get_block(p->at),
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700512 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 */
Mingming Cao617ba132006-10-11 01:20:53 -0700526static inline struct ext4_dir_entry_2 *ext4_next_entry(struct ext4_dir_entry_2 *p)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700527{
Mingming Cao617ba132006-10-11 01:20:53 -0700528 return (struct ext4_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700529}
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;
Mingming Cao617ba132006-10-11 01:20:53 -0700542 struct ext4_dir_entry_2 *de, *top;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700543 int err, count = 0;
544
545 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
Mingming Cao617ba132006-10-11 01:20:53 -0700546 if (!(bh = ext4_bread (NULL, dir, block, 0, &err)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700547 return err;
548
Mingming Cao617ba132006-10-11 01:20:53 -0700549 de = (struct ext4_dir_entry_2 *) bh->b_data;
550 top = (struct ext4_dir_entry_2 *) ((char *) de +
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700551 dir->i_sb->s_blocksize -
Mingming Cao617ba132006-10-11 01:20:53 -0700552 EXT4_DIR_REC_LEN(0));
553 for (; de < top; de = ext4_next_entry(de)) {
Eric Sandeene6c40212006-12-06 20:36:28 -0800554 if (!ext4_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
555 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
556 +((char *)de - bh->b_data))) {
557 /* On error, skip the f_pos to the next block. */
558 dir_file->f_pos = (dir_file->f_pos |
559 (dir->i_sb->s_blocksize - 1)) + 1;
560 brelse (bh);
561 return count;
562 }
Mingming Cao617ba132006-10-11 01:20:53 -0700563 ext4fs_dirhash(de->name, de->name_len, hinfo);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700564 if ((hinfo->hash < start_hash) ||
565 ((hinfo->hash == start_hash) &&
566 (hinfo->minor_hash < start_minor_hash)))
567 continue;
568 if (de->inode == 0)
569 continue;
Mingming Cao617ba132006-10-11 01:20:53 -0700570 if ((err = ext4_htree_store_dirent(dir_file,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700571 hinfo->hash, hinfo->minor_hash, de)) != 0) {
572 brelse(bh);
573 return err;
574 }
575 count++;
576 }
577 brelse(bh);
578 return count;
579}
580
581
582/*
583 * This function fills a red-black tree with information from a
584 * directory. We start scanning the directory in hash order, starting
585 * at start_hash and start_minor_hash.
586 *
587 * This function returns the number of entries inserted into the tree,
588 * or a negative error code.
589 */
Mingming Cao617ba132006-10-11 01:20:53 -0700590int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700591 __u32 start_minor_hash, __u32 *next_hash)
592{
593 struct dx_hash_info hinfo;
Mingming Cao617ba132006-10-11 01:20:53 -0700594 struct ext4_dir_entry_2 *de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700595 struct dx_frame frames[2], *frame;
596 struct inode *dir;
597 int block, err;
598 int count = 0;
599 int ret;
600 __u32 hashval;
601
602 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
603 start_minor_hash));
Josef "Jeff" Sipek9d549892006-12-08 02:36:38 -0800604 dir = dir_file->f_path.dentry->d_inode;
Mingming Cao617ba132006-10-11 01:20:53 -0700605 if (!(EXT4_I(dir)->i_flags & EXT4_INDEX_FL)) {
606 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
607 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700608 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
609 start_hash, start_minor_hash);
610 *next_hash = ~0;
611 return count;
612 }
613 hinfo.hash = start_hash;
614 hinfo.minor_hash = 0;
Josef "Jeff" Sipek9d549892006-12-08 02:36:38 -0800615 frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700616 if (!frame)
617 return err;
618
619 /* Add '.' and '..' from the htree header */
620 if (!start_hash && !start_minor_hash) {
Mingming Cao617ba132006-10-11 01:20:53 -0700621 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
622 if ((err = ext4_htree_store_dirent(dir_file, 0, 0, de)) != 0)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700623 goto errout;
624 count++;
625 }
626 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
Mingming Cao617ba132006-10-11 01:20:53 -0700627 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
628 de = ext4_next_entry(de);
629 if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700630 goto errout;
631 count++;
632 }
633
634 while (1) {
635 block = dx_get_block(frame->at);
636 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
637 start_hash, start_minor_hash);
638 if (ret < 0) {
639 err = ret;
640 goto errout;
641 }
642 count += ret;
643 hashval = ~0;
Mingming Cao617ba132006-10-11 01:20:53 -0700644 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700645 frame, frames, &hashval);
646 *next_hash = hashval;
647 if (ret < 0) {
648 err = ret;
649 goto errout;
650 }
651 /*
652 * Stop if: (a) there are no more entries, or
653 * (b) we have inserted at least one entry and the
654 * next hash value is not a continuation
655 */
656 if ((ret == 0) ||
657 (count && ((hashval & 1) == 0)))
658 break;
659 }
660 dx_release(frames);
661 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n",
662 count, *next_hash));
663 return count;
664errout:
665 dx_release(frames);
666 return (err);
667}
668
669
670/*
671 * Directory block splitting, compacting
672 */
673
Mingming Cao617ba132006-10-11 01:20:53 -0700674static int dx_make_map (struct ext4_dir_entry_2 *de, int size,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700675 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
676{
677 int count = 0;
678 char *base = (char *) de;
679 struct dx_hash_info h = *hinfo;
680
681 while ((char *) de < base + size)
682 {
683 if (de->name_len && de->inode) {
Mingming Cao617ba132006-10-11 01:20:53 -0700684 ext4fs_dirhash(de->name, de->name_len, &h);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700685 map_tail--;
686 map_tail->hash = h.hash;
687 map_tail->offs = (u32) ((char *) de - base);
688 count++;
689 cond_resched();
690 }
691 /* XXX: do we need to check rec_len == 0 case? -Chris */
Mingming Cao617ba132006-10-11 01:20:53 -0700692 de = (struct ext4_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700693 }
694 return count;
695}
696
697static void dx_sort_map (struct dx_map_entry *map, unsigned count)
698{
Andrew Morton63f57932006-10-11 01:21:24 -0700699 struct dx_map_entry *p, *q, *top = map + count - 1;
700 int more;
701 /* Combsort until bubble sort doesn't suck */
702 while (count > 2) {
703 count = count*10/13;
704 if (count - 9 < 2) /* 9, 10 -> 11 */
705 count = 11;
706 for (p = top, q = p - count; q >= map; p--, q--)
707 if (p->hash < q->hash)
708 swap(*p, *q);
709 }
710 /* Garden variety bubble sort */
711 do {
712 more = 0;
713 q = top;
714 while (q-- > map) {
715 if (q[1].hash >= q[0].hash)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700716 continue;
Andrew Morton63f57932006-10-11 01:21:24 -0700717 swap(*(q+1), *q);
718 more = 1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700719 }
720 } while(more);
721}
722
723static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
724{
725 struct dx_entry *entries = frame->entries;
726 struct dx_entry *old = frame->at, *new = old + 1;
727 int count = dx_get_count(entries);
728
729 assert(count < dx_get_limit(entries));
730 assert(old < entries + count);
731 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
732 dx_set_hash(new, hash);
733 dx_set_block(new, block);
734 dx_set_count(entries, count + 1);
735}
736#endif
737
738
Mingming Cao617ba132006-10-11 01:20:53 -0700739static void ext4_update_dx_flag(struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700740{
Mingming Cao617ba132006-10-11 01:20:53 -0700741 if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
742 EXT4_FEATURE_COMPAT_DIR_INDEX))
743 EXT4_I(inode)->i_flags &= ~EXT4_INDEX_FL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700744}
745
746/*
Mingming Cao617ba132006-10-11 01:20:53 -0700747 * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700748 *
Mingming Cao617ba132006-10-11 01:20:53 -0700749 * `len <= EXT4_NAME_LEN' is guaranteed by caller.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700750 * `de != NULL' is guaranteed by caller.
751 */
Mingming Cao617ba132006-10-11 01:20:53 -0700752static inline int ext4_match (int len, const char * const name,
753 struct ext4_dir_entry_2 * de)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700754{
755 if (len != de->name_len)
756 return 0;
757 if (!de->inode)
758 return 0;
759 return !memcmp(name, de->name, len);
760}
761
762/*
763 * Returns 0 if not found, -1 on failure, and 1 on success
764 */
765static inline int search_dirblock(struct buffer_head * bh,
766 struct inode *dir,
767 struct dentry *dentry,
768 unsigned long offset,
Mingming Cao617ba132006-10-11 01:20:53 -0700769 struct ext4_dir_entry_2 ** res_dir)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700770{
Mingming Cao617ba132006-10-11 01:20:53 -0700771 struct ext4_dir_entry_2 * de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700772 char * dlimit;
773 int de_len;
774 const char *name = dentry->d_name.name;
775 int namelen = dentry->d_name.len;
776
Mingming Cao617ba132006-10-11 01:20:53 -0700777 de = (struct ext4_dir_entry_2 *) bh->b_data;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700778 dlimit = bh->b_data + dir->i_sb->s_blocksize;
779 while ((char *) de < dlimit) {
780 /* this code is executed quadratically often */
781 /* do minimal checking `by hand' */
782
783 if ((char *) de + namelen <= dlimit &&
Mingming Cao617ba132006-10-11 01:20:53 -0700784 ext4_match (namelen, name, de)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700785 /* found a match - just to be sure, do a full check */
Mingming Cao617ba132006-10-11 01:20:53 -0700786 if (!ext4_check_dir_entry("ext4_find_entry",
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700787 dir, de, bh, offset))
788 return -1;
789 *res_dir = de;
790 return 1;
791 }
792 /* prevent looping on a bad block */
793 de_len = le16_to_cpu(de->rec_len);
794 if (de_len <= 0)
795 return -1;
796 offset += de_len;
Mingming Cao617ba132006-10-11 01:20:53 -0700797 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700798 }
799 return 0;
800}
801
802
803/*
Mingming Cao617ba132006-10-11 01:20:53 -0700804 * ext4_find_entry()
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700805 *
806 * finds an entry in the specified directory with the wanted name. It
807 * returns the cache buffer in which the entry was found, and the entry
808 * itself (as a parameter - res_dir). It does NOT read the inode of the
809 * entry - you'll have to do that yourself if you want to.
810 *
811 * The returned buffer_head has ->b_count elevated. The caller is expected
812 * to brelse() it when appropriate.
813 */
Mingming Cao617ba132006-10-11 01:20:53 -0700814static struct buffer_head * ext4_find_entry (struct dentry *dentry,
815 struct ext4_dir_entry_2 ** res_dir)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700816{
817 struct super_block * sb;
818 struct buffer_head * bh_use[NAMEI_RA_SIZE];
819 struct buffer_head * bh, *ret = NULL;
820 unsigned long start, block, b;
821 int ra_max = 0; /* Number of bh's in the readahead
822 buffer, bh_use[] */
823 int ra_ptr = 0; /* Current index into readahead
824 buffer */
825 int num = 0;
826 int nblocks, i, err;
827 struct inode *dir = dentry->d_parent->d_inode;
828 int namelen;
829 const u8 *name;
830 unsigned blocksize;
831
832 *res_dir = NULL;
833 sb = dir->i_sb;
834 blocksize = sb->s_blocksize;
835 namelen = dentry->d_name.len;
836 name = dentry->d_name.name;
Mingming Cao617ba132006-10-11 01:20:53 -0700837 if (namelen > EXT4_NAME_LEN)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700838 return NULL;
Mingming Cao617ba132006-10-11 01:20:53 -0700839#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700840 if (is_dx(dir)) {
Mingming Cao617ba132006-10-11 01:20:53 -0700841 bh = ext4_dx_find_entry(dentry, res_dir, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700842 /*
843 * On success, or if the error was file not found,
844 * return. Otherwise, fall back to doing a search the
845 * old fashioned way.
846 */
847 if (bh || (err != ERR_BAD_DX_DIR))
848 return bh;
Mingming Cao617ba132006-10-11 01:20:53 -0700849 dxtrace(printk("ext4_find_entry: dx failed, falling back\n"));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700850 }
851#endif
Mingming Cao617ba132006-10-11 01:20:53 -0700852 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
853 start = EXT4_I(dir)->i_dir_start_lookup;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700854 if (start >= nblocks)
855 start = 0;
856 block = start;
857restart:
858 do {
859 /*
860 * We deal with the read-ahead logic here.
861 */
862 if (ra_ptr >= ra_max) {
863 /* Refill the readahead buffer */
864 ra_ptr = 0;
865 b = block;
866 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
867 /*
868 * Terminate if we reach the end of the
869 * directory and must wrap, or if our
870 * search has finished at this block.
871 */
872 if (b >= nblocks || (num && block == start)) {
873 bh_use[ra_max] = NULL;
874 break;
875 }
876 num++;
Mingming Cao617ba132006-10-11 01:20:53 -0700877 bh = ext4_getblk(NULL, dir, b++, 0, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700878 bh_use[ra_max] = bh;
879 if (bh)
880 ll_rw_block(READ_META, 1, &bh);
881 }
882 }
883 if ((bh = bh_use[ra_ptr++]) == NULL)
884 goto next;
885 wait_on_buffer(bh);
886 if (!buffer_uptodate(bh)) {
887 /* read error, skip block & hope for the best */
Mingming Cao617ba132006-10-11 01:20:53 -0700888 ext4_error(sb, __FUNCTION__, "reading directory #%lu "
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700889 "offset %lu", dir->i_ino, block);
890 brelse(bh);
891 goto next;
892 }
893 i = search_dirblock(bh, dir, dentry,
Mingming Cao617ba132006-10-11 01:20:53 -0700894 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700895 if (i == 1) {
Mingming Cao617ba132006-10-11 01:20:53 -0700896 EXT4_I(dir)->i_dir_start_lookup = block;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700897 ret = bh;
898 goto cleanup_and_exit;
899 } else {
900 brelse(bh);
901 if (i < 0)
902 goto cleanup_and_exit;
903 }
904 next:
905 if (++block >= nblocks)
906 block = 0;
907 } while (block != start);
908
909 /*
910 * If the directory has grown while we were searching, then
911 * search the last part of the directory before giving up.
912 */
913 block = nblocks;
Mingming Cao617ba132006-10-11 01:20:53 -0700914 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700915 if (block < nblocks) {
916 start = 0;
917 goto restart;
918 }
919
920cleanup_and_exit:
921 /* Clean up the read-ahead blocks */
922 for (; ra_ptr < ra_max; ra_ptr++)
923 brelse (bh_use[ra_ptr]);
924 return ret;
925}
926
Mingming Cao617ba132006-10-11 01:20:53 -0700927#ifdef CONFIG_EXT4_INDEX
928static struct buffer_head * ext4_dx_find_entry(struct dentry *dentry,
929 struct ext4_dir_entry_2 **res_dir, int *err)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700930{
931 struct super_block * sb;
932 struct dx_hash_info hinfo;
933 u32 hash;
934 struct dx_frame frames[2], *frame;
Mingming Cao617ba132006-10-11 01:20:53 -0700935 struct ext4_dir_entry_2 *de, *top;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700936 struct buffer_head *bh;
937 unsigned long block;
938 int retval;
939 int namelen = dentry->d_name.len;
940 const u8 *name = dentry->d_name.name;
941 struct inode *dir = dentry->d_parent->d_inode;
942
943 sb = dir->i_sb;
944 /* NFS may look up ".." - look at dx_root directory block */
945 if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
946 if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
947 return NULL;
948 } else {
949 frame = frames;
950 frame->bh = NULL; /* for dx_release() */
951 frame->at = (struct dx_entry *)frames; /* hack for zero entry*/
952 dx_set_block(frame->at, 0); /* dx_root block is 0 */
953 }
954 hash = hinfo.hash;
955 do {
956 block = dx_get_block(frame->at);
Mingming Cao617ba132006-10-11 01:20:53 -0700957 if (!(bh = ext4_bread (NULL,dir, block, 0, err)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700958 goto errout;
Mingming Cao617ba132006-10-11 01:20:53 -0700959 de = (struct ext4_dir_entry_2 *) bh->b_data;
960 top = (struct ext4_dir_entry_2 *) ((char *) de + sb->s_blocksize -
961 EXT4_DIR_REC_LEN(0));
962 for (; de < top; de = ext4_next_entry(de))
963 if (ext4_match (namelen, name, de)) {
964 if (!ext4_check_dir_entry("ext4_find_entry",
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700965 dir, de, bh,
Mingming Cao617ba132006-10-11 01:20:53 -0700966 (block<<EXT4_BLOCK_SIZE_BITS(sb))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700967 +((char *)de - bh->b_data))) {
968 brelse (bh);
Dmitriy Monakhovfedee542007-05-08 00:25:34 -0700969 *err = ERR_BAD_DX_DIR;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700970 goto errout;
971 }
972 *res_dir = de;
973 dx_release (frames);
974 return bh;
975 }
976 brelse (bh);
977 /* Check to see if we should continue to search */
Mingming Cao617ba132006-10-11 01:20:53 -0700978 retval = ext4_htree_next_block(dir, hash, frame,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700979 frames, NULL);
980 if (retval < 0) {
Mingming Cao617ba132006-10-11 01:20:53 -0700981 ext4_warning(sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700982 "error reading index page in directory #%lu",
983 dir->i_ino);
984 *err = retval;
985 goto errout;
986 }
987 } while (retval == 1);
988
989 *err = -ENOENT;
990errout:
991 dxtrace(printk("%s not found\n", name));
992 dx_release (frames);
993 return NULL;
994}
995#endif
996
Mingming Cao617ba132006-10-11 01:20:53 -0700997static struct dentry *ext4_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700998{
999 struct inode * inode;
Mingming Cao617ba132006-10-11 01:20:53 -07001000 struct ext4_dir_entry_2 * de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001001 struct buffer_head * bh;
1002
Mingming Cao617ba132006-10-11 01:20:53 -07001003 if (dentry->d_name.len > EXT4_NAME_LEN)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001004 return ERR_PTR(-ENAMETOOLONG);
1005
Mingming Cao617ba132006-10-11 01:20:53 -07001006 bh = ext4_find_entry(dentry, &de);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001007 inode = NULL;
1008 if (bh) {
1009 unsigned long ino = le32_to_cpu(de->inode);
1010 brelse (bh);
Mingming Cao617ba132006-10-11 01:20:53 -07001011 if (!ext4_valid_inum(dir->i_sb, ino)) {
1012 ext4_error(dir->i_sb, "ext4_lookup",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001013 "bad inode number: %lu", ino);
1014 inode = NULL;
1015 } else
1016 inode = iget(dir->i_sb, ino);
1017
1018 if (!inode)
1019 return ERR_PTR(-EACCES);
Vasily Averina6c15c22007-07-15 23:40:46 -07001020
1021 if (is_bad_inode(inode)) {
1022 iput(inode);
1023 return ERR_PTR(-ENOENT);
1024 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001025 }
1026 return d_splice_alias(inode, dentry);
1027}
1028
1029
Mingming Cao617ba132006-10-11 01:20:53 -07001030struct dentry *ext4_get_parent(struct dentry *child)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001031{
1032 unsigned long ino;
1033 struct dentry *parent;
1034 struct inode *inode;
1035 struct dentry dotdot;
Mingming Cao617ba132006-10-11 01:20:53 -07001036 struct ext4_dir_entry_2 * de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001037 struct buffer_head *bh;
1038
1039 dotdot.d_name.name = "..";
1040 dotdot.d_name.len = 2;
1041 dotdot.d_parent = child; /* confusing, isn't it! */
1042
Mingming Cao617ba132006-10-11 01:20:53 -07001043 bh = ext4_find_entry(&dotdot, &de);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001044 inode = NULL;
1045 if (!bh)
1046 return ERR_PTR(-ENOENT);
1047 ino = le32_to_cpu(de->inode);
1048 brelse(bh);
1049
Mingming Cao617ba132006-10-11 01:20:53 -07001050 if (!ext4_valid_inum(child->d_inode->i_sb, ino)) {
1051 ext4_error(child->d_inode->i_sb, "ext4_get_parent",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001052 "bad inode number: %lu", ino);
1053 inode = NULL;
1054 } else
1055 inode = iget(child->d_inode->i_sb, ino);
1056
1057 if (!inode)
1058 return ERR_PTR(-EACCES);
1059
Vasily Averina6c15c22007-07-15 23:40:46 -07001060 if (is_bad_inode(inode)) {
1061 iput(inode);
1062 return ERR_PTR(-ENOENT);
1063 }
1064
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001065 parent = d_alloc_anon(inode);
1066 if (!parent) {
1067 iput(inode);
1068 parent = ERR_PTR(-ENOMEM);
1069 }
1070 return parent;
1071}
1072
1073#define S_SHIFT 12
Mingming Cao617ba132006-10-11 01:20:53 -07001074static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
1075 [S_IFREG >> S_SHIFT] = EXT4_FT_REG_FILE,
1076 [S_IFDIR >> S_SHIFT] = EXT4_FT_DIR,
1077 [S_IFCHR >> S_SHIFT] = EXT4_FT_CHRDEV,
1078 [S_IFBLK >> S_SHIFT] = EXT4_FT_BLKDEV,
1079 [S_IFIFO >> S_SHIFT] = EXT4_FT_FIFO,
1080 [S_IFSOCK >> S_SHIFT] = EXT4_FT_SOCK,
1081 [S_IFLNK >> S_SHIFT] = EXT4_FT_SYMLINK,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001082};
1083
Mingming Cao617ba132006-10-11 01:20:53 -07001084static inline void ext4_set_de_type(struct super_block *sb,
1085 struct ext4_dir_entry_2 *de,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001086 umode_t mode) {
Mingming Cao617ba132006-10-11 01:20:53 -07001087 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
1088 de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001089}
1090
Mingming Cao617ba132006-10-11 01:20:53 -07001091#ifdef CONFIG_EXT4_INDEX
1092static struct ext4_dir_entry_2 *
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001093dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
1094{
1095 unsigned rec_len = 0;
1096
1097 while (count--) {
Mingming Cao617ba132006-10-11 01:20:53 -07001098 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) (from + map->offs);
1099 rec_len = EXT4_DIR_REC_LEN(de->name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001100 memcpy (to, de, rec_len);
Mingming Cao617ba132006-10-11 01:20:53 -07001101 ((struct ext4_dir_entry_2 *) to)->rec_len =
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001102 cpu_to_le16(rec_len);
1103 de->inode = 0;
1104 map++;
1105 to += rec_len;
1106 }
Mingming Cao617ba132006-10-11 01:20:53 -07001107 return (struct ext4_dir_entry_2 *) (to - rec_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001108}
1109
Mingming Cao617ba132006-10-11 01:20:53 -07001110static struct ext4_dir_entry_2* dx_pack_dirents(char *base, int size)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001111{
Mingming Cao617ba132006-10-11 01:20:53 -07001112 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001113 unsigned rec_len = 0;
1114
1115 prev = to = de;
1116 while ((char*)de < base + size) {
Mingming Cao617ba132006-10-11 01:20:53 -07001117 next = (struct ext4_dir_entry_2 *) ((char *) de +
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001118 le16_to_cpu(de->rec_len));
1119 if (de->inode && de->name_len) {
Mingming Cao617ba132006-10-11 01:20:53 -07001120 rec_len = EXT4_DIR_REC_LEN(de->name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001121 if (de > to)
1122 memmove(to, de, rec_len);
1123 to->rec_len = cpu_to_le16(rec_len);
1124 prev = to;
Mingming Cao617ba132006-10-11 01:20:53 -07001125 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001126 }
1127 de = next;
1128 }
1129 return prev;
1130}
1131
Mingming Cao617ba132006-10-11 01:20:53 -07001132static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001133 struct buffer_head **bh,struct dx_frame *frame,
1134 struct dx_hash_info *hinfo, int *error)
1135{
1136 unsigned blocksize = dir->i_sb->s_blocksize;
1137 unsigned count, continued;
1138 struct buffer_head *bh2;
1139 u32 newblock;
1140 u32 hash2;
1141 struct dx_map_entry *map;
1142 char *data1 = (*bh)->b_data, *data2;
1143 unsigned split;
Mingming Cao617ba132006-10-11 01:20:53 -07001144 struct ext4_dir_entry_2 *de = NULL, *de2;
Dmitriy Monakhovfedee542007-05-08 00:25:34 -07001145 int err = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001146
Dmitriy Monakhovfedee542007-05-08 00:25:34 -07001147 bh2 = ext4_append (handle, dir, &newblock, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001148 if (!(bh2)) {
1149 brelse(*bh);
1150 *bh = NULL;
1151 goto errout;
1152 }
1153
1154 BUFFER_TRACE(*bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001155 err = ext4_journal_get_write_access(handle, *bh);
Dmitriy Monakhovfedee542007-05-08 00:25:34 -07001156 if (err)
1157 goto journal_error;
1158
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001159 BUFFER_TRACE(frame->bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001160 err = ext4_journal_get_write_access(handle, frame->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001161 if (err)
1162 goto journal_error;
1163
1164 data2 = bh2->b_data;
1165
1166 /* create map in the end of data2 block */
1167 map = (struct dx_map_entry *) (data2 + blocksize);
Mingming Cao617ba132006-10-11 01:20:53 -07001168 count = dx_make_map ((struct ext4_dir_entry_2 *) data1,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001169 blocksize, hinfo, map);
1170 map -= count;
1171 split = count/2; // need to adjust to actual middle
1172 dx_sort_map (map, count);
1173 hash2 = map[split].hash;
1174 continued = hash2 == map[split - 1].hash;
1175 dxtrace(printk("Split block %i at %x, %i/%i\n",
1176 dx_get_block(frame->at), hash2, split, count-split));
1177
1178 /* Fancy dance to stay within two buffers */
1179 de2 = dx_move_dirents(data1, data2, map + split, count - split);
1180 de = dx_pack_dirents(data1,blocksize);
1181 de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
1182 de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2);
Mingming Cao617ba132006-10-11 01:20:53 -07001183 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
1184 dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001185
1186 /* Which block gets the new entry? */
1187 if (hinfo->hash >= hash2)
1188 {
1189 swap(*bh, bh2);
1190 de = de2;
1191 }
1192 dx_insert_block (frame, hash2 + continued, newblock);
Mingming Cao617ba132006-10-11 01:20:53 -07001193 err = ext4_journal_dirty_metadata (handle, bh2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001194 if (err)
1195 goto journal_error;
Mingming Cao617ba132006-10-11 01:20:53 -07001196 err = ext4_journal_dirty_metadata (handle, frame->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001197 if (err)
1198 goto journal_error;
1199 brelse (bh2);
1200 dxtrace(dx_show_index ("frame", frame->entries));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001201 return de;
Dmitriy Monakhovfedee542007-05-08 00:25:34 -07001202
1203journal_error:
1204 brelse(*bh);
1205 brelse(bh2);
1206 *bh = NULL;
1207 ext4_std_error(dir->i_sb, err);
1208errout:
1209 *error = err;
1210 return NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001211}
1212#endif
1213
1214
1215/*
1216 * Add a new entry into a directory (leaf) block. If de is non-NULL,
1217 * it points to a directory entry which is guaranteed to be large
1218 * enough for new directory entry. If de is NULL, then
1219 * add_dirent_to_buf will attempt search the directory block for
1220 * space. It will return -ENOSPC if no space is available, and -EIO
1221 * and -EEXIST if directory entry already exists.
1222 *
1223 * NOTE! bh is NOT released in the case where ENOSPC is returned. In
1224 * all other cases bh is released.
1225 */
1226static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
Mingming Cao617ba132006-10-11 01:20:53 -07001227 struct inode *inode, struct ext4_dir_entry_2 *de,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001228 struct buffer_head * bh)
1229{
1230 struct inode *dir = dentry->d_parent->d_inode;
1231 const char *name = dentry->d_name.name;
1232 int namelen = dentry->d_name.len;
1233 unsigned long offset = 0;
1234 unsigned short reclen;
1235 int nlen, rlen, err;
1236 char *top;
1237
Mingming Cao617ba132006-10-11 01:20:53 -07001238 reclen = EXT4_DIR_REC_LEN(namelen);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001239 if (!de) {
Mingming Cao617ba132006-10-11 01:20:53 -07001240 de = (struct ext4_dir_entry_2 *)bh->b_data;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001241 top = bh->b_data + dir->i_sb->s_blocksize - reclen;
1242 while ((char *) de <= top) {
Mingming Cao617ba132006-10-11 01:20:53 -07001243 if (!ext4_check_dir_entry("ext4_add_entry", dir, de,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001244 bh, offset)) {
1245 brelse (bh);
1246 return -EIO;
1247 }
Mingming Cao617ba132006-10-11 01:20:53 -07001248 if (ext4_match (namelen, name, de)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001249 brelse (bh);
1250 return -EEXIST;
1251 }
Mingming Cao617ba132006-10-11 01:20:53 -07001252 nlen = EXT4_DIR_REC_LEN(de->name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001253 rlen = le16_to_cpu(de->rec_len);
1254 if ((de->inode? rlen - nlen: rlen) >= reclen)
1255 break;
Mingming Cao617ba132006-10-11 01:20:53 -07001256 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001257 offset += rlen;
1258 }
1259 if ((char *) de > top)
1260 return -ENOSPC;
1261 }
1262 BUFFER_TRACE(bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001263 err = ext4_journal_get_write_access(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001264 if (err) {
Mingming Cao617ba132006-10-11 01:20:53 -07001265 ext4_std_error(dir->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001266 brelse(bh);
1267 return err;
1268 }
1269
1270 /* By now the buffer is marked for journaling */
Mingming Cao617ba132006-10-11 01:20:53 -07001271 nlen = EXT4_DIR_REC_LEN(de->name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001272 rlen = le16_to_cpu(de->rec_len);
1273 if (de->inode) {
Mingming Cao617ba132006-10-11 01:20:53 -07001274 struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001275 de1->rec_len = cpu_to_le16(rlen - nlen);
1276 de->rec_len = cpu_to_le16(nlen);
1277 de = de1;
1278 }
Mingming Cao617ba132006-10-11 01:20:53 -07001279 de->file_type = EXT4_FT_UNKNOWN;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001280 if (inode) {
1281 de->inode = cpu_to_le32(inode->i_ino);
Mingming Cao617ba132006-10-11 01:20:53 -07001282 ext4_set_de_type(dir->i_sb, de, inode->i_mode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001283 } else
1284 de->inode = 0;
1285 de->name_len = namelen;
1286 memcpy (de->name, name, namelen);
1287 /*
1288 * XXX shouldn't update any times until successful
1289 * completion of syscall, but too many callers depend
1290 * on this.
1291 *
1292 * XXX similarly, too many callers depend on
Mingming Cao617ba132006-10-11 01:20:53 -07001293 * ext4_new_inode() setting the times, but error
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001294 * recovery deletes the inode, so the worst that can
1295 * happen is that the times are slightly out of date
1296 * and/or different from the directory change time.
1297 */
Kalpak Shahef7f3832007-07-18 09:15:20 -04001298 dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
Mingming Cao617ba132006-10-11 01:20:53 -07001299 ext4_update_dx_flag(dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001300 dir->i_version++;
Mingming Cao617ba132006-10-11 01:20:53 -07001301 ext4_mark_inode_dirty(handle, dir);
1302 BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
1303 err = ext4_journal_dirty_metadata(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001304 if (err)
Mingming Cao617ba132006-10-11 01:20:53 -07001305 ext4_std_error(dir->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001306 brelse(bh);
1307 return 0;
1308}
1309
Mingming Cao617ba132006-10-11 01:20:53 -07001310#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001311/*
1312 * This converts a one block unindexed directory to a 3 block indexed
1313 * directory, and adds the dentry to the indexed directory.
1314 */
1315static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
1316 struct inode *inode, struct buffer_head *bh)
1317{
1318 struct inode *dir = dentry->d_parent->d_inode;
1319 const char *name = dentry->d_name.name;
1320 int namelen = dentry->d_name.len;
1321 struct buffer_head *bh2;
1322 struct dx_root *root;
1323 struct dx_frame frames[2], *frame;
1324 struct dx_entry *entries;
Mingming Cao617ba132006-10-11 01:20:53 -07001325 struct ext4_dir_entry_2 *de, *de2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001326 char *data1, *top;
1327 unsigned len;
1328 int retval;
1329 unsigned blocksize;
1330 struct dx_hash_info hinfo;
1331 u32 block;
1332 struct fake_dirent *fde;
1333
1334 blocksize = dir->i_sb->s_blocksize;
1335 dxtrace(printk("Creating index\n"));
Mingming Cao617ba132006-10-11 01:20:53 -07001336 retval = ext4_journal_get_write_access(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001337 if (retval) {
Mingming Cao617ba132006-10-11 01:20:53 -07001338 ext4_std_error(dir->i_sb, retval);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001339 brelse(bh);
1340 return retval;
1341 }
1342 root = (struct dx_root *) bh->b_data;
1343
Mingming Cao617ba132006-10-11 01:20:53 -07001344 bh2 = ext4_append (handle, dir, &block, &retval);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001345 if (!(bh2)) {
1346 brelse(bh);
1347 return retval;
1348 }
Mingming Cao617ba132006-10-11 01:20:53 -07001349 EXT4_I(dir)->i_flags |= EXT4_INDEX_FL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001350 data1 = bh2->b_data;
1351
1352 /* The 0th block becomes the root, move the dirents out */
1353 fde = &root->dotdot;
Mingming Cao617ba132006-10-11 01:20:53 -07001354 de = (struct ext4_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001355 len = ((char *) root) + blocksize - (char *) de;
1356 memcpy (data1, de, len);
Mingming Cao617ba132006-10-11 01:20:53 -07001357 de = (struct ext4_dir_entry_2 *) data1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001358 top = data1 + len;
1359 while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top)
1360 de = de2;
1361 de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
1362 /* Initialize the root; the dot dirents already exist */
Mingming Cao617ba132006-10-11 01:20:53 -07001363 de = (struct ext4_dir_entry_2 *) (&root->dotdot);
1364 de->rec_len = cpu_to_le16(blocksize - EXT4_DIR_REC_LEN(2));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001365 memset (&root->info, 0, sizeof(root->info));
1366 root->info.info_length = sizeof(root->info);
Mingming Cao617ba132006-10-11 01:20:53 -07001367 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001368 entries = root->entries;
1369 dx_set_block (entries, 1);
1370 dx_set_count (entries, 1);
1371 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));
1372
1373 /* Initialize as for dx_probe */
1374 hinfo.hash_version = root->info.hash_version;
Mingming Cao617ba132006-10-11 01:20:53 -07001375 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
1376 ext4fs_dirhash(name, namelen, &hinfo);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001377 frame = frames;
1378 frame->entries = entries;
1379 frame->at = entries;
1380 frame->bh = bh;
1381 bh = bh2;
1382 de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
1383 dx_release (frames);
1384 if (!(de))
1385 return retval;
1386
1387 return add_dirent_to_buf(handle, dentry, inode, de, bh);
1388}
1389#endif
1390
1391/*
Mingming Cao617ba132006-10-11 01:20:53 -07001392 * ext4_add_entry()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001393 *
1394 * adds a file entry to the specified directory, using the same
Mingming Cao617ba132006-10-11 01:20:53 -07001395 * semantics as ext4_find_entry(). It returns NULL if it failed.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001396 *
1397 * NOTE!! The inode part of 'de' is left at 0 - which means you
1398 * may not sleep between calling this and putting something into
1399 * the entry, as someone else might have used it while you slept.
1400 */
Mingming Cao617ba132006-10-11 01:20:53 -07001401static int ext4_add_entry (handle_t *handle, struct dentry *dentry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001402 struct inode *inode)
1403{
1404 struct inode *dir = dentry->d_parent->d_inode;
1405 unsigned long offset;
1406 struct buffer_head * bh;
Mingming Cao617ba132006-10-11 01:20:53 -07001407 struct ext4_dir_entry_2 *de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001408 struct super_block * sb;
1409 int retval;
Mingming Cao617ba132006-10-11 01:20:53 -07001410#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001411 int dx_fallback=0;
1412#endif
1413 unsigned blocksize;
1414 u32 block, blocks;
1415
1416 sb = dir->i_sb;
1417 blocksize = sb->s_blocksize;
1418 if (!dentry->d_name.len)
1419 return -EINVAL;
Mingming Cao617ba132006-10-11 01:20:53 -07001420#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001421 if (is_dx(dir)) {
Mingming Cao617ba132006-10-11 01:20:53 -07001422 retval = ext4_dx_add_entry(handle, dentry, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001423 if (!retval || (retval != ERR_BAD_DX_DIR))
1424 return retval;
Mingming Cao617ba132006-10-11 01:20:53 -07001425 EXT4_I(dir)->i_flags &= ~EXT4_INDEX_FL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001426 dx_fallback++;
Mingming Cao617ba132006-10-11 01:20:53 -07001427 ext4_mark_inode_dirty(handle, dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001428 }
1429#endif
1430 blocks = dir->i_size >> sb->s_blocksize_bits;
1431 for (block = 0, offset = 0; block < blocks; block++) {
Mingming Cao617ba132006-10-11 01:20:53 -07001432 bh = ext4_bread(handle, dir, block, 0, &retval);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001433 if(!bh)
1434 return retval;
1435 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1436 if (retval != -ENOSPC)
1437 return retval;
1438
Mingming Cao617ba132006-10-11 01:20:53 -07001439#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001440 if (blocks == 1 && !dx_fallback &&
Mingming Cao617ba132006-10-11 01:20:53 -07001441 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001442 return make_indexed_dir(handle, dentry, inode, bh);
1443#endif
1444 brelse(bh);
1445 }
Mingming Cao617ba132006-10-11 01:20:53 -07001446 bh = ext4_append(handle, dir, &block, &retval);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001447 if (!bh)
1448 return retval;
Mingming Cao617ba132006-10-11 01:20:53 -07001449 de = (struct ext4_dir_entry_2 *) bh->b_data;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001450 de->inode = 0;
1451 de->rec_len = cpu_to_le16(blocksize);
1452 return add_dirent_to_buf(handle, dentry, inode, de, bh);
1453}
1454
Mingming Cao617ba132006-10-11 01:20:53 -07001455#ifdef CONFIG_EXT4_INDEX
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001456/*
1457 * Returns 0 for success, or a negative error value
1458 */
Mingming Cao617ba132006-10-11 01:20:53 -07001459static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001460 struct inode *inode)
1461{
1462 struct dx_frame frames[2], *frame;
1463 struct dx_entry *entries, *at;
1464 struct dx_hash_info hinfo;
1465 struct buffer_head * bh;
1466 struct inode *dir = dentry->d_parent->d_inode;
1467 struct super_block * sb = dir->i_sb;
Mingming Cao617ba132006-10-11 01:20:53 -07001468 struct ext4_dir_entry_2 *de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001469 int err;
1470
1471 frame = dx_probe(dentry, NULL, &hinfo, frames, &err);
1472 if (!frame)
1473 return err;
1474 entries = frame->entries;
1475 at = frame->at;
1476
Mingming Cao617ba132006-10-11 01:20:53 -07001477 if (!(bh = ext4_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001478 goto cleanup;
1479
1480 BUFFER_TRACE(bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001481 err = ext4_journal_get_write_access(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001482 if (err)
1483 goto journal_error;
1484
1485 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
1486 if (err != -ENOSPC) {
1487 bh = NULL;
1488 goto cleanup;
1489 }
1490
1491 /* Block full, should compress but for now just split */
1492 dxtrace(printk("using %u of %u node entries\n",
1493 dx_get_count(entries), dx_get_limit(entries)));
1494 /* Need to split index? */
1495 if (dx_get_count(entries) == dx_get_limit(entries)) {
1496 u32 newblock;
1497 unsigned icount = dx_get_count(entries);
1498 int levels = frame - frames;
1499 struct dx_entry *entries2;
1500 struct dx_node *node2;
1501 struct buffer_head *bh2;
1502
1503 if (levels && (dx_get_count(frames->entries) ==
1504 dx_get_limit(frames->entries))) {
Mingming Cao617ba132006-10-11 01:20:53 -07001505 ext4_warning(sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001506 "Directory index full!");
1507 err = -ENOSPC;
1508 goto cleanup;
1509 }
Mingming Cao617ba132006-10-11 01:20:53 -07001510 bh2 = ext4_append (handle, dir, &newblock, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001511 if (!(bh2))
1512 goto cleanup;
1513 node2 = (struct dx_node *)(bh2->b_data);
1514 entries2 = node2->entries;
1515 node2->fake.rec_len = cpu_to_le16(sb->s_blocksize);
1516 node2->fake.inode = 0;
1517 BUFFER_TRACE(frame->bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001518 err = ext4_journal_get_write_access(handle, frame->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001519 if (err)
1520 goto journal_error;
1521 if (levels) {
1522 unsigned icount1 = icount/2, icount2 = icount - icount1;
1523 unsigned hash2 = dx_get_hash(entries + icount1);
1524 dxtrace(printk("Split index %i/%i\n", icount1, icount2));
1525
1526 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
Mingming Cao617ba132006-10-11 01:20:53 -07001527 err = ext4_journal_get_write_access(handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001528 frames[0].bh);
1529 if (err)
1530 goto journal_error;
1531
1532 memcpy ((char *) entries2, (char *) (entries + icount1),
1533 icount2 * sizeof(struct dx_entry));
1534 dx_set_count (entries, icount1);
1535 dx_set_count (entries2, icount2);
1536 dx_set_limit (entries2, dx_node_limit(dir));
1537
1538 /* Which index block gets the new entry? */
1539 if (at - entries >= icount1) {
1540 frame->at = at = at - entries - icount1 + entries2;
1541 frame->entries = entries = entries2;
1542 swap(frame->bh, bh2);
1543 }
1544 dx_insert_block (frames + 0, hash2, newblock);
1545 dxtrace(dx_show_index ("node", frames[1].entries));
1546 dxtrace(dx_show_index ("node",
1547 ((struct dx_node *) bh2->b_data)->entries));
Mingming Cao617ba132006-10-11 01:20:53 -07001548 err = ext4_journal_dirty_metadata(handle, bh2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001549 if (err)
1550 goto journal_error;
1551 brelse (bh2);
1552 } else {
1553 dxtrace(printk("Creating second level index...\n"));
1554 memcpy((char *) entries2, (char *) entries,
1555 icount * sizeof(struct dx_entry));
1556 dx_set_limit(entries2, dx_node_limit(dir));
1557
1558 /* Set up root */
1559 dx_set_count(entries, 1);
1560 dx_set_block(entries + 0, newblock);
1561 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
1562
1563 /* Add new access path frame */
1564 frame = frames + 1;
1565 frame->at = at = at - entries + entries2;
1566 frame->entries = entries = entries2;
1567 frame->bh = bh2;
Mingming Cao617ba132006-10-11 01:20:53 -07001568 err = ext4_journal_get_write_access(handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001569 frame->bh);
1570 if (err)
1571 goto journal_error;
1572 }
Mingming Cao617ba132006-10-11 01:20:53 -07001573 ext4_journal_dirty_metadata(handle, frames[0].bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001574 }
1575 de = do_split(handle, dir, &bh, frame, &hinfo, &err);
1576 if (!de)
1577 goto cleanup;
1578 err = add_dirent_to_buf(handle, dentry, inode, de, bh);
1579 bh = NULL;
1580 goto cleanup;
1581
1582journal_error:
Mingming Cao617ba132006-10-11 01:20:53 -07001583 ext4_std_error(dir->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001584cleanup:
1585 if (bh)
1586 brelse(bh);
1587 dx_release(frames);
1588 return err;
1589}
1590#endif
1591
1592/*
Mingming Cao617ba132006-10-11 01:20:53 -07001593 * ext4_delete_entry deletes a directory entry by merging it with the
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001594 * previous entry
1595 */
Mingming Cao617ba132006-10-11 01:20:53 -07001596static int ext4_delete_entry (handle_t *handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001597 struct inode * dir,
Mingming Cao617ba132006-10-11 01:20:53 -07001598 struct ext4_dir_entry_2 * de_del,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001599 struct buffer_head * bh)
1600{
Mingming Cao617ba132006-10-11 01:20:53 -07001601 struct ext4_dir_entry_2 * de, * pde;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001602 int i;
1603
1604 i = 0;
1605 pde = NULL;
Mingming Cao617ba132006-10-11 01:20:53 -07001606 de = (struct ext4_dir_entry_2 *) bh->b_data;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001607 while (i < bh->b_size) {
Mingming Cao617ba132006-10-11 01:20:53 -07001608 if (!ext4_check_dir_entry("ext4_delete_entry", dir, de, bh, i))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001609 return -EIO;
1610 if (de == de_del) {
1611 BUFFER_TRACE(bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001612 ext4_journal_get_write_access(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001613 if (pde)
1614 pde->rec_len =
1615 cpu_to_le16(le16_to_cpu(pde->rec_len) +
1616 le16_to_cpu(de->rec_len));
1617 else
1618 de->inode = 0;
1619 dir->i_version++;
Mingming Cao617ba132006-10-11 01:20:53 -07001620 BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
1621 ext4_journal_dirty_metadata(handle, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001622 return 0;
1623 }
1624 i += le16_to_cpu(de->rec_len);
1625 pde = de;
Mingming Cao617ba132006-10-11 01:20:53 -07001626 de = (struct ext4_dir_entry_2 *)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001627 ((char *) de + le16_to_cpu(de->rec_len));
1628 }
1629 return -ENOENT;
1630}
1631
Andreas Dilgerf8628a12007-07-18 08:38:01 -04001632/*
1633 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2,
1634 * since this indicates that nlinks count was previously 1.
1635 */
1636static void ext4_inc_count(handle_t *handle, struct inode *inode)
1637{
1638 inc_nlink(inode);
1639 if (is_dx(inode) && inode->i_nlink > 1) {
1640 /* limit is 16-bit i_links_count */
1641 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) {
1642 inode->i_nlink = 1;
1643 EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb,
1644 EXT4_FEATURE_RO_COMPAT_DIR_NLINK);
1645 }
1646 }
1647}
1648
1649/*
1650 * If a directory had nlink == 1, then we should let it be 1. This indicates
1651 * directory has >EXT4_LINK_MAX subdirs.
1652 */
1653static void ext4_dec_count(handle_t *handle, struct inode *inode)
1654{
1655 drop_nlink(inode);
1656 if (S_ISDIR(inode->i_mode) && inode->i_nlink == 0)
1657 inc_nlink(inode);
1658}
1659
1660
Mingming Cao617ba132006-10-11 01:20:53 -07001661static int ext4_add_nondir(handle_t *handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001662 struct dentry *dentry, struct inode *inode)
1663{
Mingming Cao617ba132006-10-11 01:20:53 -07001664 int err = ext4_add_entry(handle, dentry, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001665 if (!err) {
Mingming Cao617ba132006-10-11 01:20:53 -07001666 ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001667 d_instantiate(dentry, inode);
1668 return 0;
1669 }
Eric Sandeen731b9a52007-02-10 01:46:16 -08001670 drop_nlink(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001671 iput(inode);
1672 return err;
1673}
1674
1675/*
1676 * By the time this is called, we already have created
1677 * the directory cache entry for the new file, but it
1678 * is so far negative - it has no inode.
1679 *
1680 * If the create succeeds, we fill in the inode information
1681 * with d_instantiate().
1682 */
Mingming Cao617ba132006-10-11 01:20:53 -07001683static int ext4_create (struct inode * dir, struct dentry * dentry, int mode,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001684 struct nameidata *nd)
1685{
1686 handle_t *handle;
1687 struct inode * inode;
1688 int err, retries = 0;
1689
1690retry:
Mingming Cao617ba132006-10-11 01:20:53 -07001691 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
1692 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1693 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001694 if (IS_ERR(handle))
1695 return PTR_ERR(handle);
1696
1697 if (IS_DIRSYNC(dir))
1698 handle->h_sync = 1;
1699
Mingming Cao617ba132006-10-11 01:20:53 -07001700 inode = ext4_new_inode (handle, dir, mode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001701 err = PTR_ERR(inode);
1702 if (!IS_ERR(inode)) {
Mingming Cao617ba132006-10-11 01:20:53 -07001703 inode->i_op = &ext4_file_inode_operations;
1704 inode->i_fop = &ext4_file_operations;
1705 ext4_set_aops(inode);
1706 err = ext4_add_nondir(handle, dentry, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001707 }
Mingming Cao617ba132006-10-11 01:20:53 -07001708 ext4_journal_stop(handle);
1709 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001710 goto retry;
1711 return err;
1712}
1713
Mingming Cao617ba132006-10-11 01:20:53 -07001714static int ext4_mknod (struct inode * dir, struct dentry *dentry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001715 int mode, dev_t rdev)
1716{
1717 handle_t *handle;
1718 struct inode *inode;
1719 int err, retries = 0;
1720
1721 if (!new_valid_dev(rdev))
1722 return -EINVAL;
1723
1724retry:
Mingming Cao617ba132006-10-11 01:20:53 -07001725 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
1726 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1727 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001728 if (IS_ERR(handle))
1729 return PTR_ERR(handle);
1730
1731 if (IS_DIRSYNC(dir))
1732 handle->h_sync = 1;
1733
Mingming Cao617ba132006-10-11 01:20:53 -07001734 inode = ext4_new_inode (handle, dir, mode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001735 err = PTR_ERR(inode);
1736 if (!IS_ERR(inode)) {
1737 init_special_inode(inode, inode->i_mode, rdev);
Mingming Cao617ba132006-10-11 01:20:53 -07001738#ifdef CONFIG_EXT4DEV_FS_XATTR
1739 inode->i_op = &ext4_special_inode_operations;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001740#endif
Mingming Cao617ba132006-10-11 01:20:53 -07001741 err = ext4_add_nondir(handle, dentry, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001742 }
Mingming Cao617ba132006-10-11 01:20:53 -07001743 ext4_journal_stop(handle);
1744 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001745 goto retry;
1746 return err;
1747}
1748
Mingming Cao617ba132006-10-11 01:20:53 -07001749static int ext4_mkdir(struct inode * dir, struct dentry * dentry, int mode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001750{
1751 handle_t *handle;
1752 struct inode * inode;
1753 struct buffer_head * dir_block;
Mingming Cao617ba132006-10-11 01:20:53 -07001754 struct ext4_dir_entry_2 * de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001755 int err, retries = 0;
1756
Andreas Dilgerf8628a12007-07-18 08:38:01 -04001757 if (EXT4_DIR_LINK_MAX(dir))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001758 return -EMLINK;
1759
1760retry:
Mingming Cao617ba132006-10-11 01:20:53 -07001761 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
1762 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
1763 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001764 if (IS_ERR(handle))
1765 return PTR_ERR(handle);
1766
1767 if (IS_DIRSYNC(dir))
1768 handle->h_sync = 1;
1769
Mingming Cao617ba132006-10-11 01:20:53 -07001770 inode = ext4_new_inode (handle, dir, S_IFDIR | mode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001771 err = PTR_ERR(inode);
1772 if (IS_ERR(inode))
1773 goto out_stop;
1774
Mingming Cao617ba132006-10-11 01:20:53 -07001775 inode->i_op = &ext4_dir_inode_operations;
1776 inode->i_fop = &ext4_dir_operations;
1777 inode->i_size = EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1778 dir_block = ext4_bread (handle, inode, 0, 1, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001779 if (!dir_block) {
Andreas Dilgerf8628a12007-07-18 08:38:01 -04001780 ext4_dec_count(handle, inode); /* is this nlink == 0? */
Mingming Cao617ba132006-10-11 01:20:53 -07001781 ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001782 iput (inode);
1783 goto out_stop;
1784 }
1785 BUFFER_TRACE(dir_block, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07001786 ext4_journal_get_write_access(handle, dir_block);
1787 de = (struct ext4_dir_entry_2 *) dir_block->b_data;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001788 de->inode = cpu_to_le32(inode->i_ino);
1789 de->name_len = 1;
Mingming Cao617ba132006-10-11 01:20:53 -07001790 de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(de->name_len));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001791 strcpy (de->name, ".");
Mingming Cao617ba132006-10-11 01:20:53 -07001792 ext4_set_de_type(dir->i_sb, de, S_IFDIR);
1793 de = (struct ext4_dir_entry_2 *)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001794 ((char *) de + le16_to_cpu(de->rec_len));
1795 de->inode = cpu_to_le32(dir->i_ino);
Mingming Cao617ba132006-10-11 01:20:53 -07001796 de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT4_DIR_REC_LEN(1));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001797 de->name_len = 2;
1798 strcpy (de->name, "..");
Mingming Cao617ba132006-10-11 01:20:53 -07001799 ext4_set_de_type(dir->i_sb, de, S_IFDIR);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001800 inode->i_nlink = 2;
Mingming Cao617ba132006-10-11 01:20:53 -07001801 BUFFER_TRACE(dir_block, "call ext4_journal_dirty_metadata");
1802 ext4_journal_dirty_metadata(handle, dir_block);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001803 brelse (dir_block);
Mingming Cao617ba132006-10-11 01:20:53 -07001804 ext4_mark_inode_dirty(handle, inode);
1805 err = ext4_add_entry (handle, dentry, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001806 if (err) {
1807 inode->i_nlink = 0;
Mingming Cao617ba132006-10-11 01:20:53 -07001808 ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001809 iput (inode);
1810 goto out_stop;
1811 }
Andreas Dilgerf8628a12007-07-18 08:38:01 -04001812 ext4_inc_count(handle, dir);
Mingming Cao617ba132006-10-11 01:20:53 -07001813 ext4_update_dx_flag(dir);
1814 ext4_mark_inode_dirty(handle, dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001815 d_instantiate(dentry, inode);
1816out_stop:
Mingming Cao617ba132006-10-11 01:20:53 -07001817 ext4_journal_stop(handle);
1818 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001819 goto retry;
1820 return err;
1821}
1822
1823/*
1824 * routine to check that the specified directory is empty (for rmdir)
1825 */
1826static int empty_dir (struct inode * inode)
1827{
1828 unsigned long offset;
1829 struct buffer_head * bh;
Mingming Cao617ba132006-10-11 01:20:53 -07001830 struct ext4_dir_entry_2 * de, * de1;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001831 struct super_block * sb;
1832 int err = 0;
1833
1834 sb = inode->i_sb;
Mingming Cao617ba132006-10-11 01:20:53 -07001835 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2) ||
1836 !(bh = ext4_bread (NULL, inode, 0, 0, &err))) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001837 if (err)
Mingming Cao617ba132006-10-11 01:20:53 -07001838 ext4_error(inode->i_sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001839 "error %d reading directory #%lu offset 0",
1840 err, inode->i_ino);
1841 else
Mingming Cao617ba132006-10-11 01:20:53 -07001842 ext4_warning(inode->i_sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001843 "bad directory (dir #%lu) - no data block",
1844 inode->i_ino);
1845 return 1;
1846 }
Mingming Cao617ba132006-10-11 01:20:53 -07001847 de = (struct ext4_dir_entry_2 *) bh->b_data;
1848 de1 = (struct ext4_dir_entry_2 *)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001849 ((char *) de + le16_to_cpu(de->rec_len));
1850 if (le32_to_cpu(de->inode) != inode->i_ino ||
1851 !le32_to_cpu(de1->inode) ||
1852 strcmp (".", de->name) ||
1853 strcmp ("..", de1->name)) {
Mingming Cao617ba132006-10-11 01:20:53 -07001854 ext4_warning (inode->i_sb, "empty_dir",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001855 "bad directory (dir #%lu) - no `.' or `..'",
1856 inode->i_ino);
1857 brelse (bh);
1858 return 1;
1859 }
1860 offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
Mingming Cao617ba132006-10-11 01:20:53 -07001861 de = (struct ext4_dir_entry_2 *)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001862 ((char *) de1 + le16_to_cpu(de1->rec_len));
1863 while (offset < inode->i_size ) {
1864 if (!bh ||
1865 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
1866 err = 0;
1867 brelse (bh);
Mingming Cao617ba132006-10-11 01:20:53 -07001868 bh = ext4_bread (NULL, inode,
1869 offset >> EXT4_BLOCK_SIZE_BITS(sb), 0, &err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001870 if (!bh) {
1871 if (err)
Mingming Cao617ba132006-10-11 01:20:53 -07001872 ext4_error(sb, __FUNCTION__,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001873 "error %d reading directory"
1874 " #%lu offset %lu",
1875 err, inode->i_ino, offset);
1876 offset += sb->s_blocksize;
1877 continue;
1878 }
Mingming Cao617ba132006-10-11 01:20:53 -07001879 de = (struct ext4_dir_entry_2 *) bh->b_data;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001880 }
Mingming Cao617ba132006-10-11 01:20:53 -07001881 if (!ext4_check_dir_entry("empty_dir", inode, de, bh, offset)) {
1882 de = (struct ext4_dir_entry_2 *)(bh->b_data +
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001883 sb->s_blocksize);
1884 offset = (offset | (sb->s_blocksize - 1)) + 1;
1885 continue;
1886 }
1887 if (le32_to_cpu(de->inode)) {
1888 brelse (bh);
1889 return 0;
1890 }
1891 offset += le16_to_cpu(de->rec_len);
Mingming Cao617ba132006-10-11 01:20:53 -07001892 de = (struct ext4_dir_entry_2 *)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001893 ((char *) de + le16_to_cpu(de->rec_len));
1894 }
1895 brelse (bh);
1896 return 1;
1897}
1898
Mingming Cao617ba132006-10-11 01:20:53 -07001899/* ext4_orphan_add() links an unlinked or truncated inode into a list of
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001900 * such inodes, starting at the superblock, in case we crash before the
1901 * file is closed/deleted, or in case the inode truncate spans multiple
1902 * transactions and the last transaction is not recovered after a crash.
1903 *
1904 * At filesystem recovery time, we walk this list deleting unlinked
Mingming Cao617ba132006-10-11 01:20:53 -07001905 * inodes and truncating linked inodes in ext4_orphan_cleanup().
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001906 */
Mingming Cao617ba132006-10-11 01:20:53 -07001907int ext4_orphan_add(handle_t *handle, struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001908{
1909 struct super_block *sb = inode->i_sb;
Mingming Cao617ba132006-10-11 01:20:53 -07001910 struct ext4_iloc iloc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001911 int err = 0, rc;
1912
1913 lock_super(sb);
Mingming Cao617ba132006-10-11 01:20:53 -07001914 if (!list_empty(&EXT4_I(inode)->i_orphan))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001915 goto out_unlock;
1916
1917 /* Orphan handling is only valid for files with data blocks
1918 * being truncated, or files being unlinked. */
1919
1920 /* @@@ FIXME: Observation from aviro:
Mingming Cao617ba132006-10-11 01:20:53 -07001921 * I think I can trigger J_ASSERT in ext4_orphan_add(). We block
1922 * here (on lock_super()), so race with ext4_link() which might bump
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001923 * ->i_nlink. For, say it, character device. Not a regular file,
1924 * not a directory, not a symlink and ->i_nlink > 0.
1925 */
1926 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1927 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
1928
Mingming Cao617ba132006-10-11 01:20:53 -07001929 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
1930 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001931 if (err)
1932 goto out_unlock;
1933
Mingming Cao617ba132006-10-11 01:20:53 -07001934 err = ext4_reserve_inode_write(handle, inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001935 if (err)
1936 goto out_unlock;
1937
1938 /* Insert this inode at the head of the on-disk orphan list... */
Mingming Cao617ba132006-10-11 01:20:53 -07001939 NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan);
1940 EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
1941 err = ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
1942 rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001943 if (!err)
1944 err = rc;
1945
1946 /* Only add to the head of the in-memory list if all the
1947 * previous operations succeeded. If the orphan_add is going to
1948 * fail (possibly taking the journal offline), we can't risk
1949 * leaving the inode on the orphan list: stray orphan-list
1950 * entries can cause panics at unmount time.
1951 *
1952 * This is safe: on error we're going to ignore the orphan list
1953 * anyway on the next recovery. */
1954 if (!err)
Mingming Cao617ba132006-10-11 01:20:53 -07001955 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001956
1957 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
1958 jbd_debug(4, "orphan inode %lu will point to %d\n",
1959 inode->i_ino, NEXT_ORPHAN(inode));
1960out_unlock:
1961 unlock_super(sb);
Mingming Cao617ba132006-10-11 01:20:53 -07001962 ext4_std_error(inode->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001963 return err;
1964}
1965
1966/*
Mingming Cao617ba132006-10-11 01:20:53 -07001967 * ext4_orphan_del() removes an unlinked or truncated inode from the list
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001968 * of such inodes stored on disk, because it is finally being cleaned up.
1969 */
Mingming Cao617ba132006-10-11 01:20:53 -07001970int ext4_orphan_del(handle_t *handle, struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001971{
1972 struct list_head *prev;
Mingming Cao617ba132006-10-11 01:20:53 -07001973 struct ext4_inode_info *ei = EXT4_I(inode);
1974 struct ext4_sb_info *sbi;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001975 unsigned long ino_next;
Mingming Cao617ba132006-10-11 01:20:53 -07001976 struct ext4_iloc iloc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001977 int err = 0;
1978
1979 lock_super(inode->i_sb);
1980 if (list_empty(&ei->i_orphan)) {
1981 unlock_super(inode->i_sb);
1982 return 0;
1983 }
1984
1985 ino_next = NEXT_ORPHAN(inode);
1986 prev = ei->i_orphan.prev;
Mingming Cao617ba132006-10-11 01:20:53 -07001987 sbi = EXT4_SB(inode->i_sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001988
1989 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
1990
1991 list_del_init(&ei->i_orphan);
1992
1993 /* If we're on an error path, we may not have a valid
1994 * transaction handle with which to update the orphan list on
1995 * disk, but we still need to remove the inode from the linked
1996 * list in memory. */
1997 if (!handle)
1998 goto out;
1999
Mingming Cao617ba132006-10-11 01:20:53 -07002000 err = ext4_reserve_inode_write(handle, inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002001 if (err)
2002 goto out_err;
2003
2004 if (prev == &sbi->s_orphan) {
2005 jbd_debug(4, "superblock will point to %lu\n", ino_next);
2006 BUFFER_TRACE(sbi->s_sbh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07002007 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002008 if (err)
2009 goto out_brelse;
2010 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
Mingming Cao617ba132006-10-11 01:20:53 -07002011 err = ext4_journal_dirty_metadata(handle, sbi->s_sbh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002012 } else {
Mingming Cao617ba132006-10-11 01:20:53 -07002013 struct ext4_iloc iloc2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002014 struct inode *i_prev =
Mingming Cao617ba132006-10-11 01:20:53 -07002015 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002016
2017 jbd_debug(4, "orphan inode %lu will point to %lu\n",
2018 i_prev->i_ino, ino_next);
Mingming Cao617ba132006-10-11 01:20:53 -07002019 err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002020 if (err)
2021 goto out_brelse;
2022 NEXT_ORPHAN(i_prev) = ino_next;
Mingming Cao617ba132006-10-11 01:20:53 -07002023 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002024 }
2025 if (err)
2026 goto out_brelse;
2027 NEXT_ORPHAN(inode) = 0;
Mingming Cao617ba132006-10-11 01:20:53 -07002028 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002029
2030out_err:
Mingming Cao617ba132006-10-11 01:20:53 -07002031 ext4_std_error(inode->i_sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002032out:
2033 unlock_super(inode->i_sb);
2034 return err;
2035
2036out_brelse:
2037 brelse(iloc.bh);
2038 goto out_err;
2039}
2040
Mingming Cao617ba132006-10-11 01:20:53 -07002041static int ext4_rmdir (struct inode * dir, struct dentry *dentry)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002042{
2043 int retval;
2044 struct inode * inode;
2045 struct buffer_head * bh;
Mingming Cao617ba132006-10-11 01:20:53 -07002046 struct ext4_dir_entry_2 * de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002047 handle_t *handle;
2048
2049 /* Initialize quotas before so that eventual writes go in
2050 * separate transaction */
2051 DQUOT_INIT(dentry->d_inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002052 handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002053 if (IS_ERR(handle))
2054 return PTR_ERR(handle);
2055
2056 retval = -ENOENT;
Mingming Cao617ba132006-10-11 01:20:53 -07002057 bh = ext4_find_entry (dentry, &de);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002058 if (!bh)
2059 goto end_rmdir;
2060
2061 if (IS_DIRSYNC(dir))
2062 handle->h_sync = 1;
2063
2064 inode = dentry->d_inode;
2065
2066 retval = -EIO;
2067 if (le32_to_cpu(de->inode) != inode->i_ino)
2068 goto end_rmdir;
2069
2070 retval = -ENOTEMPTY;
2071 if (!empty_dir (inode))
2072 goto end_rmdir;
2073
Mingming Cao617ba132006-10-11 01:20:53 -07002074 retval = ext4_delete_entry(handle, dir, de, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002075 if (retval)
2076 goto end_rmdir;
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002077 if (!EXT4_DIR_LINK_EMPTY(inode))
Mingming Cao617ba132006-10-11 01:20:53 -07002078 ext4_warning (inode->i_sb, "ext4_rmdir",
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002079 "empty directory has too many links (%d)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002080 inode->i_nlink);
2081 inode->i_version++;
2082 clear_nlink(inode);
2083 /* There's no need to set i_disksize: the fact that i_nlink is
2084 * zero will ensure that the right thing happens during any
2085 * recovery. */
2086 inode->i_size = 0;
Mingming Cao617ba132006-10-11 01:20:53 -07002087 ext4_orphan_add(handle, inode);
Kalpak Shahef7f3832007-07-18 09:15:20 -04002088 inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002089 ext4_mark_inode_dirty(handle, inode);
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002090 ext4_dec_count(handle, dir);
Mingming Cao617ba132006-10-11 01:20:53 -07002091 ext4_update_dx_flag(dir);
2092 ext4_mark_inode_dirty(handle, dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002093
2094end_rmdir:
Mingming Cao617ba132006-10-11 01:20:53 -07002095 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002096 brelse (bh);
2097 return retval;
2098}
2099
Mingming Cao617ba132006-10-11 01:20:53 -07002100static int ext4_unlink(struct inode * dir, struct dentry *dentry)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002101{
2102 int retval;
2103 struct inode * inode;
2104 struct buffer_head * bh;
Mingming Cao617ba132006-10-11 01:20:53 -07002105 struct ext4_dir_entry_2 * de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002106 handle_t *handle;
2107
2108 /* Initialize quotas before so that eventual writes go
2109 * in separate transaction */
2110 DQUOT_INIT(dentry->d_inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002111 handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002112 if (IS_ERR(handle))
2113 return PTR_ERR(handle);
2114
2115 if (IS_DIRSYNC(dir))
2116 handle->h_sync = 1;
2117
2118 retval = -ENOENT;
Mingming Cao617ba132006-10-11 01:20:53 -07002119 bh = ext4_find_entry (dentry, &de);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002120 if (!bh)
2121 goto end_unlink;
2122
2123 inode = dentry->d_inode;
2124
2125 retval = -EIO;
2126 if (le32_to_cpu(de->inode) != inode->i_ino)
2127 goto end_unlink;
2128
2129 if (!inode->i_nlink) {
Mingming Cao617ba132006-10-11 01:20:53 -07002130 ext4_warning (inode->i_sb, "ext4_unlink",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002131 "Deleting nonexistent file (%lu), %d",
2132 inode->i_ino, inode->i_nlink);
2133 inode->i_nlink = 1;
2134 }
Mingming Cao617ba132006-10-11 01:20:53 -07002135 retval = ext4_delete_entry(handle, dir, de, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002136 if (retval)
2137 goto end_unlink;
Kalpak Shahef7f3832007-07-18 09:15:20 -04002138 dir->i_ctime = dir->i_mtime = ext4_current_time(dir);
Mingming Cao617ba132006-10-11 01:20:53 -07002139 ext4_update_dx_flag(dir);
2140 ext4_mark_inode_dirty(handle, dir);
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002141 ext4_dec_count(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002142 if (!inode->i_nlink)
Mingming Cao617ba132006-10-11 01:20:53 -07002143 ext4_orphan_add(handle, inode);
Kalpak Shahef7f3832007-07-18 09:15:20 -04002144 inode->i_ctime = ext4_current_time(inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002145 ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002146 retval = 0;
2147
2148end_unlink:
Mingming Cao617ba132006-10-11 01:20:53 -07002149 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002150 brelse (bh);
2151 return retval;
2152}
2153
Mingming Cao617ba132006-10-11 01:20:53 -07002154static int ext4_symlink (struct inode * dir,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002155 struct dentry *dentry, const char * symname)
2156{
2157 handle_t *handle;
2158 struct inode * inode;
2159 int l, err, retries = 0;
2160
2161 l = strlen(symname)+1;
2162 if (l > dir->i_sb->s_blocksize)
2163 return -ENAMETOOLONG;
2164
2165retry:
Mingming Cao617ba132006-10-11 01:20:53 -07002166 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2167 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 5 +
2168 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002169 if (IS_ERR(handle))
2170 return PTR_ERR(handle);
2171
2172 if (IS_DIRSYNC(dir))
2173 handle->h_sync = 1;
2174
Mingming Cao617ba132006-10-11 01:20:53 -07002175 inode = ext4_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002176 err = PTR_ERR(inode);
2177 if (IS_ERR(inode))
2178 goto out_stop;
2179
Mingming Cao617ba132006-10-11 01:20:53 -07002180 if (l > sizeof (EXT4_I(inode)->i_data)) {
2181 inode->i_op = &ext4_symlink_inode_operations;
2182 ext4_set_aops(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002183 /*
Mingming Cao617ba132006-10-11 01:20:53 -07002184 * page_symlink() calls into ext4_prepare/commit_write.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002185 * We have a transaction open. All is sweetness. It also sets
2186 * i_size in generic_commit_write().
2187 */
2188 err = __page_symlink(inode, symname, l,
2189 mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
2190 if (err) {
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002191 ext4_dec_count(handle, inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002192 ext4_mark_inode_dirty(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002193 iput (inode);
2194 goto out_stop;
2195 }
2196 } else {
Mingming Cao617ba132006-10-11 01:20:53 -07002197 inode->i_op = &ext4_fast_symlink_inode_operations;
2198 memcpy((char*)&EXT4_I(inode)->i_data,symname,l);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002199 inode->i_size = l-1;
2200 }
Mingming Cao617ba132006-10-11 01:20:53 -07002201 EXT4_I(inode)->i_disksize = inode->i_size;
2202 err = ext4_add_nondir(handle, dentry, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002203out_stop:
Mingming Cao617ba132006-10-11 01:20:53 -07002204 ext4_journal_stop(handle);
2205 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002206 goto retry;
2207 return err;
2208}
2209
Mingming Cao617ba132006-10-11 01:20:53 -07002210static int ext4_link (struct dentry * old_dentry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002211 struct inode * dir, struct dentry *dentry)
2212{
2213 handle_t *handle;
2214 struct inode *inode = old_dentry->d_inode;
2215 int err, retries = 0;
2216
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002217 if (EXT4_DIR_LINK_MAX(inode))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002218 return -EMLINK;
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002219
Eric Sandeen2988a772007-02-10 01:46:16 -08002220 /*
2221 * Return -ENOENT if we've raced with unlink and i_nlink is 0. Doing
2222 * otherwise has the potential to corrupt the orphan inode list.
2223 */
2224 if (inode->i_nlink == 0)
2225 return -ENOENT;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002226
2227retry:
Mingming Cao617ba132006-10-11 01:20:53 -07002228 handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
2229 EXT4_INDEX_EXTRA_TRANS_BLOCKS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002230 if (IS_ERR(handle))
2231 return PTR_ERR(handle);
2232
2233 if (IS_DIRSYNC(dir))
2234 handle->h_sync = 1;
2235
Kalpak Shahef7f3832007-07-18 09:15:20 -04002236 inode->i_ctime = ext4_current_time(inode);
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002237 ext4_inc_count(handle, inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002238 atomic_inc(&inode->i_count);
2239
Mingming Cao617ba132006-10-11 01:20:53 -07002240 err = ext4_add_nondir(handle, dentry, inode);
2241 ext4_journal_stop(handle);
2242 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002243 goto retry;
2244 return err;
2245}
2246
2247#define PARENT_INO(buffer) \
Mingming Cao617ba132006-10-11 01:20:53 -07002248 ((struct ext4_dir_entry_2 *) ((char *) buffer + \
2249 le16_to_cpu(((struct ext4_dir_entry_2 *) buffer)->rec_len)))->inode
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002250
2251/*
2252 * Anybody can rename anything with this: the permission checks are left to the
2253 * higher-level routines.
2254 */
Mingming Cao617ba132006-10-11 01:20:53 -07002255static int ext4_rename (struct inode * old_dir, struct dentry *old_dentry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002256 struct inode * new_dir,struct dentry *new_dentry)
2257{
2258 handle_t *handle;
2259 struct inode * old_inode, * new_inode;
2260 struct buffer_head * old_bh, * new_bh, * dir_bh;
Mingming Cao617ba132006-10-11 01:20:53 -07002261 struct ext4_dir_entry_2 * old_de, * new_de;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002262 int retval;
2263
2264 old_bh = new_bh = dir_bh = NULL;
2265
2266 /* Initialize quotas before so that eventual writes go
2267 * in separate transaction */
2268 if (new_dentry->d_inode)
2269 DQUOT_INIT(new_dentry->d_inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002270 handle = ext4_journal_start(old_dir, 2 *
2271 EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) +
2272 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002273 if (IS_ERR(handle))
2274 return PTR_ERR(handle);
2275
2276 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
2277 handle->h_sync = 1;
2278
Mingming Cao617ba132006-10-11 01:20:53 -07002279 old_bh = ext4_find_entry (old_dentry, &old_de);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002280 /*
2281 * Check for inode number is _not_ due to possible IO errors.
2282 * We might rmdir the source, keep it as pwd of some process
2283 * and merrily kill the link to whatever was created under the
2284 * same name. Goodbye sticky bit ;-<
2285 */
2286 old_inode = old_dentry->d_inode;
2287 retval = -ENOENT;
2288 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
2289 goto end_rename;
2290
2291 new_inode = new_dentry->d_inode;
Mingming Cao617ba132006-10-11 01:20:53 -07002292 new_bh = ext4_find_entry (new_dentry, &new_de);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002293 if (new_bh) {
2294 if (!new_inode) {
2295 brelse (new_bh);
2296 new_bh = NULL;
2297 }
2298 }
2299 if (S_ISDIR(old_inode->i_mode)) {
2300 if (new_inode) {
2301 retval = -ENOTEMPTY;
2302 if (!empty_dir (new_inode))
2303 goto end_rename;
2304 }
2305 retval = -EIO;
Mingming Cao617ba132006-10-11 01:20:53 -07002306 dir_bh = ext4_bread (handle, old_inode, 0, 0, &retval);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002307 if (!dir_bh)
2308 goto end_rename;
2309 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
2310 goto end_rename;
2311 retval = -EMLINK;
2312 if (!new_inode && new_dir!=old_dir &&
Mingming Cao617ba132006-10-11 01:20:53 -07002313 new_dir->i_nlink >= EXT4_LINK_MAX)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002314 goto end_rename;
2315 }
2316 if (!new_bh) {
Mingming Cao617ba132006-10-11 01:20:53 -07002317 retval = ext4_add_entry (handle, new_dentry, old_inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002318 if (retval)
2319 goto end_rename;
2320 } else {
2321 BUFFER_TRACE(new_bh, "get write access");
Mingming Cao617ba132006-10-11 01:20:53 -07002322 ext4_journal_get_write_access(handle, new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002323 new_de->inode = cpu_to_le32(old_inode->i_ino);
Mingming Cao617ba132006-10-11 01:20:53 -07002324 if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
2325 EXT4_FEATURE_INCOMPAT_FILETYPE))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002326 new_de->file_type = old_de->file_type;
2327 new_dir->i_version++;
Mingming Cao617ba132006-10-11 01:20:53 -07002328 BUFFER_TRACE(new_bh, "call ext4_journal_dirty_metadata");
2329 ext4_journal_dirty_metadata(handle, new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002330 brelse(new_bh);
2331 new_bh = NULL;
2332 }
2333
2334 /*
2335 * Like most other Unix systems, set the ctime for inodes on a
2336 * rename.
2337 */
Kalpak Shahef7f3832007-07-18 09:15:20 -04002338 old_inode->i_ctime = ext4_current_time(old_inode);
Mingming Cao617ba132006-10-11 01:20:53 -07002339 ext4_mark_inode_dirty(handle, old_inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002340
2341 /*
2342 * ok, that's it
2343 */
2344 if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
2345 old_de->name_len != old_dentry->d_name.len ||
2346 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
Mingming Cao617ba132006-10-11 01:20:53 -07002347 (retval = ext4_delete_entry(handle, old_dir,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002348 old_de, old_bh)) == -ENOENT) {
2349 /* old_de could have moved from under us during htree split, so
2350 * make sure that we are deleting the right entry. We might
2351 * also be pointing to a stale entry in the unused part of
2352 * old_bh so just checking inum and the name isn't enough. */
2353 struct buffer_head *old_bh2;
Mingming Cao617ba132006-10-11 01:20:53 -07002354 struct ext4_dir_entry_2 *old_de2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002355
Mingming Cao617ba132006-10-11 01:20:53 -07002356 old_bh2 = ext4_find_entry(old_dentry, &old_de2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002357 if (old_bh2) {
Mingming Cao617ba132006-10-11 01:20:53 -07002358 retval = ext4_delete_entry(handle, old_dir,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002359 old_de2, old_bh2);
2360 brelse(old_bh2);
2361 }
2362 }
2363 if (retval) {
Mingming Cao617ba132006-10-11 01:20:53 -07002364 ext4_warning(old_dir->i_sb, "ext4_rename",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002365 "Deleting old file (%lu), %d, error=%d",
2366 old_dir->i_ino, old_dir->i_nlink, retval);
2367 }
2368
2369 if (new_inode) {
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002370 ext4_dec_count(handle, new_inode);
Kalpak Shahef7f3832007-07-18 09:15:20 -04002371 new_inode->i_ctime = ext4_current_time(new_inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002372 }
Kalpak Shahef7f3832007-07-18 09:15:20 -04002373 old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir);
Mingming Cao617ba132006-10-11 01:20:53 -07002374 ext4_update_dx_flag(old_dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002375 if (dir_bh) {
2376 BUFFER_TRACE(dir_bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -07002377 ext4_journal_get_write_access(handle, dir_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002378 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
Mingming Cao617ba132006-10-11 01:20:53 -07002379 BUFFER_TRACE(dir_bh, "call ext4_journal_dirty_metadata");
2380 ext4_journal_dirty_metadata(handle, dir_bh);
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002381 ext4_dec_count(handle, old_dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002382 if (new_inode) {
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002383 /* checked empty_dir above, can't have another parent,
2384 * ext3_dec_count() won't work for many-linked dirs */
2385 new_inode->i_nlink = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002386 } else {
Andreas Dilgerf8628a12007-07-18 08:38:01 -04002387 ext4_inc_count(handle, new_dir);
Mingming Cao617ba132006-10-11 01:20:53 -07002388 ext4_update_dx_flag(new_dir);
2389 ext4_mark_inode_dirty(handle, new_dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002390 }
2391 }
Mingming Cao617ba132006-10-11 01:20:53 -07002392 ext4_mark_inode_dirty(handle, old_dir);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002393 if (new_inode) {
Mingming Cao617ba132006-10-11 01:20:53 -07002394 ext4_mark_inode_dirty(handle, new_inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002395 if (!new_inode->i_nlink)
Mingming Cao617ba132006-10-11 01:20:53 -07002396 ext4_orphan_add(handle, new_inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002397 }
2398 retval = 0;
2399
2400end_rename:
2401 brelse (dir_bh);
2402 brelse (old_bh);
2403 brelse (new_bh);
Mingming Cao617ba132006-10-11 01:20:53 -07002404 ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002405 return retval;
2406}
2407
2408/*
2409 * directories can handle most operations...
2410 */
Arjan van de Ven754661f2007-02-12 00:55:38 -08002411const struct inode_operations ext4_dir_inode_operations = {
Mingming Cao617ba132006-10-11 01:20:53 -07002412 .create = ext4_create,
2413 .lookup = ext4_lookup,
2414 .link = ext4_link,
2415 .unlink = ext4_unlink,
2416 .symlink = ext4_symlink,
2417 .mkdir = ext4_mkdir,
2418 .rmdir = ext4_rmdir,
2419 .mknod = ext4_mknod,
2420 .rename = ext4_rename,
2421 .setattr = ext4_setattr,
2422#ifdef CONFIG_EXT4DEV_FS_XATTR
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002423 .setxattr = generic_setxattr,
2424 .getxattr = generic_getxattr,
Mingming Cao617ba132006-10-11 01:20:53 -07002425 .listxattr = ext4_listxattr,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002426 .removexattr = generic_removexattr,
2427#endif
Mingming Cao617ba132006-10-11 01:20:53 -07002428 .permission = ext4_permission,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002429};
2430
Arjan van de Ven754661f2007-02-12 00:55:38 -08002431const struct inode_operations ext4_special_inode_operations = {
Mingming Cao617ba132006-10-11 01:20:53 -07002432 .setattr = ext4_setattr,
2433#ifdef CONFIG_EXT4DEV_FS_XATTR
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002434 .setxattr = generic_setxattr,
2435 .getxattr = generic_getxattr,
Mingming Cao617ba132006-10-11 01:20:53 -07002436 .listxattr = ext4_listxattr,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002437 .removexattr = generic_removexattr,
2438#endif
Mingming Cao617ba132006-10-11 01:20:53 -07002439 .permission = ext4_permission,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07002440};