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Commit | Line | Data |
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ac27a0ec | 1 | /* |
617ba13b | 2 | * linux/fs/ext4/dir.c |
ac27a0ec DK |
3 | * |
4 | * Copyright (C) 1992, 1993, 1994, 1995 | |
5 | * Remy Card (card@masi.ibp.fr) | |
6 | * Laboratoire MASI - Institut Blaise Pascal | |
7 | * Universite Pierre et Marie Curie (Paris VI) | |
8 | * | |
9 | * from | |
10 | * | |
11 | * linux/fs/minix/dir.c | |
12 | * | |
13 | * Copyright (C) 1991, 1992 Linus Torvalds | |
14 | * | |
617ba13b | 15 | * ext4 directory handling functions |
ac27a0ec DK |
16 | * |
17 | * Big-endian to little-endian byte-swapping/bitmaps by | |
18 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
19 | * | |
20 | * Hash Tree Directory indexing (c) 2001 Daniel Phillips | |
21 | * | |
22 | */ | |
23 | ||
24 | #include <linux/fs.h> | |
dab291af | 25 | #include <linux/jbd2.h> |
ac27a0ec | 26 | #include <linux/buffer_head.h> |
ac27a0ec DK |
27 | #include <linux/slab.h> |
28 | #include <linux/rbtree.h> | |
3dcf5451 | 29 | #include "ext4.h" |
65d165d9 | 30 | #include "xattr.h" |
ac27a0ec | 31 | |
af5bc92d TT |
32 | static int ext4_dx_readdir(struct file *filp, |
33 | void *dirent, filldir_t filldir); | |
ac27a0ec | 34 | |
d1f5273e FY |
35 | /** |
36 | * Check if the given dir-inode refers to an htree-indexed directory | |
37 | * (or a directory which chould potentially get coverted to use htree | |
38 | * indexing). | |
39 | * | |
40 | * Return 1 if it is a dx dir, 0 if not | |
41 | */ | |
42 | static int is_dx_dir(struct inode *inode) | |
43 | { | |
44 | struct super_block *sb = inode->i_sb; | |
45 | ||
46 | if (EXT4_HAS_COMPAT_FEATURE(inode->i_sb, | |
47 | EXT4_FEATURE_COMPAT_DIR_INDEX) && | |
48 | ((ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) || | |
8af0f082 TM |
49 | ((inode->i_size >> sb->s_blocksize_bits) == 1) || |
50 | ext4_has_inline_data(inode))) | |
d1f5273e FY |
51 | return 1; |
52 | ||
53 | return 0; | |
54 | } | |
55 | ||
cad3f007 TT |
56 | /* |
57 | * Return 0 if the directory entry is OK, and 1 if there is a problem | |
58 | * | |
59 | * Note: this is the opposite of what ext2 and ext3 historically returned... | |
65d165d9 TM |
60 | * |
61 | * bh passed here can be an inode block or a dir data block, depending | |
62 | * on the inode inline data flag. | |
cad3f007 | 63 | */ |
60fd4da3 | 64 | int __ext4_check_dir_entry(const char *function, unsigned int line, |
f7c21177 | 65 | struct inode *dir, struct file *filp, |
60fd4da3 | 66 | struct ext4_dir_entry_2 *de, |
226ba972 | 67 | struct buffer_head *bh, char *buf, int size, |
60fd4da3 | 68 | unsigned int offset) |
ac27a0ec | 69 | { |
af5bc92d | 70 | const char *error_msg = NULL; |
3d0518f4 WY |
71 | const int rlen = ext4_rec_len_from_disk(de->rec_len, |
72 | dir->i_sb->s_blocksize); | |
ac27a0ec | 73 | |
cad3f007 | 74 | if (unlikely(rlen < EXT4_DIR_REC_LEN(1))) |
ac27a0ec | 75 | error_msg = "rec_len is smaller than minimal"; |
cad3f007 | 76 | else if (unlikely(rlen % 4 != 0)) |
ac27a0ec | 77 | error_msg = "rec_len % 4 != 0"; |
cad3f007 | 78 | else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len))) |
ac27a0ec | 79 | error_msg = "rec_len is too small for name_len"; |
226ba972 TM |
80 | else if (unlikely(((char *) de - buf) + rlen > size)) |
81 | error_msg = "directory entry across range"; | |
cad3f007 TT |
82 | else if (unlikely(le32_to_cpu(de->inode) > |
83 | le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))) | |
ac27a0ec | 84 | error_msg = "inode out of bounds"; |
cad3f007 TT |
85 | else |
86 | return 0; | |
87 | ||
f7c21177 | 88 | if (filp) |
4fda4003 | 89 | ext4_error_file(filp, function, line, bh->b_blocknr, |
f7c21177 TT |
90 | "bad entry in directory: %s - offset=%u(%u), " |
91 | "inode=%u, rec_len=%d, name_len=%d", | |
226ba972 | 92 | error_msg, (unsigned) (offset % size), |
f7c21177 TT |
93 | offset, le32_to_cpu(de->inode), |
94 | rlen, de->name_len); | |
95 | else | |
4fda4003 | 96 | ext4_error_inode(dir, function, line, bh->b_blocknr, |
f7c21177 TT |
97 | "bad entry in directory: %s - offset=%u(%u), " |
98 | "inode=%u, rec_len=%d, name_len=%d", | |
226ba972 | 99 | error_msg, (unsigned) (offset % size), |
f7c21177 TT |
100 | offset, le32_to_cpu(de->inode), |
101 | rlen, de->name_len); | |
102 | ||
cad3f007 | 103 | return 1; |
ac27a0ec DK |
104 | } |
105 | ||
af5bc92d TT |
106 | static int ext4_readdir(struct file *filp, |
107 | void *dirent, filldir_t filldir) | |
ac27a0ec DK |
108 | { |
109 | int error = 0; | |
498e5f24 | 110 | unsigned int offset; |
ac27a0ec | 111 | int i, stored; |
617ba13b | 112 | struct ext4_dir_entry_2 *de; |
ac27a0ec | 113 | int err; |
496ad9aa | 114 | struct inode *inode = file_inode(filp); |
d1f5273e | 115 | struct super_block *sb = inode->i_sb; |
ac27a0ec | 116 | int ret = 0; |
9d9f1775 | 117 | int dir_has_error = 0; |
ac27a0ec | 118 | |
d1f5273e | 119 | if (is_dx_dir(inode)) { |
617ba13b | 120 | err = ext4_dx_readdir(filp, dirent, filldir); |
ac27a0ec DK |
121 | if (err != ERR_BAD_DX_DIR) { |
122 | ret = err; | |
123 | goto out; | |
124 | } | |
125 | /* | |
126 | * We don't set the inode dirty flag since it's not | |
127 | * critical that it get flushed back to the disk. | |
128 | */ | |
496ad9aa | 129 | ext4_clear_inode_flag(file_inode(filp), |
07a03824 | 130 | EXT4_INODE_INDEX); |
ac27a0ec | 131 | } |
8af0f082 TM |
132 | |
133 | if (ext4_has_inline_data(inode)) { | |
134 | int has_inline_data = 1; | |
135 | ret = ext4_read_inline_dir(filp, dirent, filldir, | |
136 | &has_inline_data); | |
137 | if (has_inline_data) | |
138 | return ret; | |
139 | } | |
140 | ||
ac27a0ec DK |
141 | stored = 0; |
142 | offset = filp->f_pos & (sb->s_blocksize - 1); | |
143 | ||
144 | while (!error && !stored && filp->f_pos < inode->i_size) { | |
2ed88685 | 145 | struct ext4_map_blocks map; |
ac27a0ec DK |
146 | struct buffer_head *bh = NULL; |
147 | ||
2ed88685 TT |
148 | map.m_lblk = filp->f_pos >> EXT4_BLOCK_SIZE_BITS(sb); |
149 | map.m_len = 1; | |
150 | err = ext4_map_blocks(NULL, inode, &map, 0); | |
ac27a0ec | 151 | if (err > 0) { |
2ed88685 | 152 | pgoff_t index = map.m_pblk >> |
dc7868fc FW |
153 | (PAGE_CACHE_SHIFT - inode->i_blkbits); |
154 | if (!ra_has_index(&filp->f_ra, index)) | |
cf914a7d | 155 | page_cache_sync_readahead( |
dc7868fc FW |
156 | sb->s_bdev->bd_inode->i_mapping, |
157 | &filp->f_ra, filp, | |
cf914a7d | 158 | index, 1); |
f4e6b498 | 159 | filp->f_ra.prev_pos = (loff_t)index << PAGE_CACHE_SHIFT; |
2ed88685 | 160 | bh = ext4_bread(NULL, inode, map.m_lblk, 0, &err); |
ac27a0ec DK |
161 | } |
162 | ||
163 | /* | |
164 | * We ignore I/O errors on directories so users have a chance | |
165 | * of recovering data when there's a bad sector | |
166 | */ | |
167 | if (!bh) { | |
9d9f1775 | 168 | if (!dir_has_error) { |
f7c21177 TT |
169 | EXT4_ERROR_FILE(filp, 0, |
170 | "directory contains a " | |
171 | "hole at offset %llu", | |
9d9f1775 ES |
172 | (unsigned long long) filp->f_pos); |
173 | dir_has_error = 1; | |
174 | } | |
e6c40211 ES |
175 | /* corrupt size? Maybe no more blocks to read */ |
176 | if (filp->f_pos > inode->i_blocks << 9) | |
177 | break; | |
ac27a0ec DK |
178 | filp->f_pos += sb->s_blocksize - offset; |
179 | continue; | |
180 | } | |
181 | ||
b0336e8d DW |
182 | /* Check the checksum */ |
183 | if (!buffer_verified(bh) && | |
184 | !ext4_dirent_csum_verify(inode, | |
185 | (struct ext4_dir_entry *)bh->b_data)) { | |
186 | EXT4_ERROR_FILE(filp, 0, "directory fails checksum " | |
187 | "at offset %llu", | |
188 | (unsigned long long)filp->f_pos); | |
189 | filp->f_pos += sb->s_blocksize - offset; | |
d5ac7773 | 190 | brelse(bh); |
b0336e8d DW |
191 | continue; |
192 | } | |
193 | set_buffer_verified(bh); | |
194 | ||
ac27a0ec DK |
195 | revalidate: |
196 | /* If the dir block has changed since the last call to | |
197 | * readdir(2), then we might be pointing to an invalid | |
198 | * dirent right now. Scan from the start of the block | |
199 | * to make sure. */ | |
200 | if (filp->f_version != inode->i_version) { | |
201 | for (i = 0; i < sb->s_blocksize && i < offset; ) { | |
617ba13b | 202 | de = (struct ext4_dir_entry_2 *) |
ac27a0ec DK |
203 | (bh->b_data + i); |
204 | /* It's too expensive to do a full | |
205 | * dirent test each time round this | |
206 | * loop, but we do have to test at | |
207 | * least that it is non-zero. A | |
208 | * failure will be detected in the | |
209 | * dirent test below. */ | |
3d0518f4 WY |
210 | if (ext4_rec_len_from_disk(de->rec_len, |
211 | sb->s_blocksize) < EXT4_DIR_REC_LEN(1)) | |
ac27a0ec | 212 | break; |
3d0518f4 WY |
213 | i += ext4_rec_len_from_disk(de->rec_len, |
214 | sb->s_blocksize); | |
ac27a0ec DK |
215 | } |
216 | offset = i; | |
217 | filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1)) | |
218 | | offset; | |
219 | filp->f_version = inode->i_version; | |
220 | } | |
221 | ||
222 | while (!error && filp->f_pos < inode->i_size | |
223 | && offset < sb->s_blocksize) { | |
617ba13b | 224 | de = (struct ext4_dir_entry_2 *) (bh->b_data + offset); |
226ba972 TM |
225 | if (ext4_check_dir_entry(inode, filp, de, bh, |
226 | bh->b_data, bh->b_size, | |
227 | offset)) { | |
63f57933 AM |
228 | /* |
229 | * On error, skip the f_pos to the next block | |
230 | */ | |
ac27a0ec DK |
231 | filp->f_pos = (filp->f_pos | |
232 | (sb->s_blocksize - 1)) + 1; | |
af5bc92d | 233 | brelse(bh); |
ac27a0ec DK |
234 | ret = stored; |
235 | goto out; | |
236 | } | |
3d0518f4 WY |
237 | offset += ext4_rec_len_from_disk(de->rec_len, |
238 | sb->s_blocksize); | |
ac27a0ec DK |
239 | if (le32_to_cpu(de->inode)) { |
240 | /* We might block in the next section | |
241 | * if the data destination is | |
242 | * currently swapped out. So, use a | |
243 | * version stamp to detect whether or | |
244 | * not the directory has been modified | |
245 | * during the copy operation. | |
246 | */ | |
2b47c361 | 247 | u64 version = filp->f_version; |
ac27a0ec DK |
248 | |
249 | error = filldir(dirent, de->name, | |
250 | de->name_len, | |
251 | filp->f_pos, | |
252 | le32_to_cpu(de->inode), | |
253 | get_dtype(sb, de->file_type)); | |
254 | if (error) | |
255 | break; | |
256 | if (version != filp->f_version) | |
257 | goto revalidate; | |
af5bc92d | 258 | stored++; |
ac27a0ec | 259 | } |
3d0518f4 WY |
260 | filp->f_pos += ext4_rec_len_from_disk(de->rec_len, |
261 | sb->s_blocksize); | |
ac27a0ec DK |
262 | } |
263 | offset = 0; | |
af5bc92d | 264 | brelse(bh); |
ac27a0ec DK |
265 | } |
266 | out: | |
267 | return ret; | |
268 | } | |
269 | ||
d1f5273e FY |
270 | static inline int is_32bit_api(void) |
271 | { | |
272 | #ifdef CONFIG_COMPAT | |
273 | return is_compat_task(); | |
274 | #else | |
275 | return (BITS_PER_LONG == 32); | |
276 | #endif | |
277 | } | |
278 | ||
ac27a0ec DK |
279 | /* |
280 | * These functions convert from the major/minor hash to an f_pos | |
d1f5273e FY |
281 | * value for dx directories |
282 | * | |
283 | * Upper layer (for example NFS) should specify FMODE_32BITHASH or | |
284 | * FMODE_64BITHASH explicitly. On the other hand, we allow ext4 to be mounted | |
285 | * directly on both 32-bit and 64-bit nodes, under such case, neither | |
286 | * FMODE_32BITHASH nor FMODE_64BITHASH is specified. | |
287 | */ | |
288 | static inline loff_t hash2pos(struct file *filp, __u32 major, __u32 minor) | |
289 | { | |
290 | if ((filp->f_mode & FMODE_32BITHASH) || | |
291 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) | |
292 | return major >> 1; | |
293 | else | |
294 | return ((__u64)(major >> 1) << 32) | (__u64)minor; | |
295 | } | |
296 | ||
297 | static inline __u32 pos2maj_hash(struct file *filp, loff_t pos) | |
298 | { | |
299 | if ((filp->f_mode & FMODE_32BITHASH) || | |
300 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) | |
301 | return (pos << 1) & 0xffffffff; | |
302 | else | |
303 | return ((pos >> 32) << 1) & 0xffffffff; | |
304 | } | |
305 | ||
306 | static inline __u32 pos2min_hash(struct file *filp, loff_t pos) | |
307 | { | |
308 | if ((filp->f_mode & FMODE_32BITHASH) || | |
309 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) | |
310 | return 0; | |
311 | else | |
312 | return pos & 0xffffffff; | |
313 | } | |
314 | ||
315 | /* | |
316 | * Return 32- or 64-bit end-of-file for dx directories | |
317 | */ | |
318 | static inline loff_t ext4_get_htree_eof(struct file *filp) | |
319 | { | |
320 | if ((filp->f_mode & FMODE_32BITHASH) || | |
321 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) | |
322 | return EXT4_HTREE_EOF_32BIT; | |
323 | else | |
324 | return EXT4_HTREE_EOF_64BIT; | |
325 | } | |
326 | ||
327 | ||
328 | /* | |
ec7268ce ES |
329 | * ext4_dir_llseek() calls generic_file_llseek_size to handle htree |
330 | * directories, where the "offset" is in terms of the filename hash | |
331 | * value instead of the byte offset. | |
ac27a0ec | 332 | * |
ec7268ce ES |
333 | * Because we may return a 64-bit hash that is well beyond offset limits, |
334 | * we need to pass the max hash as the maximum allowable offset in | |
335 | * the htree directory case. | |
336 | * | |
337 | * For non-htree, ext4_llseek already chooses the proper max offset. | |
ac27a0ec | 338 | */ |
d4e43954 | 339 | static loff_t ext4_dir_llseek(struct file *file, loff_t offset, int whence) |
d1f5273e FY |
340 | { |
341 | struct inode *inode = file->f_mapping->host; | |
d1f5273e | 342 | int dx_dir = is_dx_dir(inode); |
ec7268ce | 343 | loff_t htree_max = ext4_get_htree_eof(file); |
d1f5273e | 344 | |
ec7268ce | 345 | if (likely(dx_dir)) |
965c8e59 | 346 | return generic_file_llseek_size(file, offset, whence, |
ec7268ce ES |
347 | htree_max, htree_max); |
348 | else | |
965c8e59 | 349 | return ext4_llseek(file, offset, whence); |
d1f5273e | 350 | } |
ac27a0ec DK |
351 | |
352 | /* | |
353 | * This structure holds the nodes of the red-black tree used to store | |
354 | * the directory entry in hash order. | |
355 | */ | |
356 | struct fname { | |
357 | __u32 hash; | |
358 | __u32 minor_hash; | |
359 | struct rb_node rb_hash; | |
360 | struct fname *next; | |
361 | __u32 inode; | |
362 | __u8 name_len; | |
363 | __u8 file_type; | |
364 | char name[0]; | |
365 | }; | |
366 | ||
367 | /* | |
368 | * This functoin implements a non-recursive way of freeing all of the | |
369 | * nodes in the red-black tree. | |
370 | */ | |
371 | static void free_rb_tree_fname(struct rb_root *root) | |
372 | { | |
373 | struct rb_node *n = root->rb_node; | |
374 | struct rb_node *parent; | |
375 | struct fname *fname; | |
376 | ||
377 | while (n) { | |
378 | /* Do the node's children first */ | |
69baee06 | 379 | if (n->rb_left) { |
ac27a0ec DK |
380 | n = n->rb_left; |
381 | continue; | |
382 | } | |
383 | if (n->rb_right) { | |
384 | n = n->rb_right; | |
385 | continue; | |
386 | } | |
387 | /* | |
388 | * The node has no children; free it, and then zero | |
389 | * out parent's link to it. Finally go to the | |
390 | * beginning of the loop and try to free the parent | |
391 | * node. | |
392 | */ | |
393 | parent = rb_parent(n); | |
394 | fname = rb_entry(n, struct fname, rb_hash); | |
395 | while (fname) { | |
af5bc92d | 396 | struct fname *old = fname; |
ac27a0ec | 397 | fname = fname->next; |
af5bc92d | 398 | kfree(old); |
ac27a0ec DK |
399 | } |
400 | if (!parent) | |
64e290ec | 401 | *root = RB_ROOT; |
ac27a0ec DK |
402 | else if (parent->rb_left == n) |
403 | parent->rb_left = NULL; | |
404 | else if (parent->rb_right == n) | |
405 | parent->rb_right = NULL; | |
406 | n = parent; | |
407 | } | |
ac27a0ec DK |
408 | } |
409 | ||
410 | ||
d1f5273e FY |
411 | static struct dir_private_info *ext4_htree_create_dir_info(struct file *filp, |
412 | loff_t pos) | |
ac27a0ec DK |
413 | { |
414 | struct dir_private_info *p; | |
415 | ||
69baee06 | 416 | p = kzalloc(sizeof(struct dir_private_info), GFP_KERNEL); |
ac27a0ec DK |
417 | if (!p) |
418 | return NULL; | |
d1f5273e FY |
419 | p->curr_hash = pos2maj_hash(filp, pos); |
420 | p->curr_minor_hash = pos2min_hash(filp, pos); | |
ac27a0ec DK |
421 | return p; |
422 | } | |
423 | ||
617ba13b | 424 | void ext4_htree_free_dir_info(struct dir_private_info *p) |
ac27a0ec DK |
425 | { |
426 | free_rb_tree_fname(&p->root); | |
427 | kfree(p); | |
428 | } | |
429 | ||
430 | /* | |
431 | * Given a directory entry, enter it into the fname rb tree. | |
432 | */ | |
617ba13b | 433 | int ext4_htree_store_dirent(struct file *dir_file, __u32 hash, |
ac27a0ec | 434 | __u32 minor_hash, |
617ba13b | 435 | struct ext4_dir_entry_2 *dirent) |
ac27a0ec DK |
436 | { |
437 | struct rb_node **p, *parent = NULL; | |
af5bc92d | 438 | struct fname *fname, *new_fn; |
ac27a0ec DK |
439 | struct dir_private_info *info; |
440 | int len; | |
441 | ||
a271fe85 | 442 | info = dir_file->private_data; |
ac27a0ec DK |
443 | p = &info->root.rb_node; |
444 | ||
445 | /* Create and allocate the fname structure */ | |
446 | len = sizeof(struct fname) + dirent->name_len + 1; | |
447 | new_fn = kzalloc(len, GFP_KERNEL); | |
448 | if (!new_fn) | |
449 | return -ENOMEM; | |
450 | new_fn->hash = hash; | |
451 | new_fn->minor_hash = minor_hash; | |
452 | new_fn->inode = le32_to_cpu(dirent->inode); | |
453 | new_fn->name_len = dirent->name_len; | |
454 | new_fn->file_type = dirent->file_type; | |
455 | memcpy(new_fn->name, dirent->name, dirent->name_len); | |
456 | new_fn->name[dirent->name_len] = 0; | |
457 | ||
458 | while (*p) { | |
459 | parent = *p; | |
460 | fname = rb_entry(parent, struct fname, rb_hash); | |
461 | ||
462 | /* | |
463 | * If the hash and minor hash match up, then we put | |
464 | * them on a linked list. This rarely happens... | |
465 | */ | |
466 | if ((new_fn->hash == fname->hash) && | |
467 | (new_fn->minor_hash == fname->minor_hash)) { | |
468 | new_fn->next = fname->next; | |
469 | fname->next = new_fn; | |
470 | return 0; | |
471 | } | |
472 | ||
473 | if (new_fn->hash < fname->hash) | |
474 | p = &(*p)->rb_left; | |
475 | else if (new_fn->hash > fname->hash) | |
476 | p = &(*p)->rb_right; | |
477 | else if (new_fn->minor_hash < fname->minor_hash) | |
478 | p = &(*p)->rb_left; | |
479 | else /* if (new_fn->minor_hash > fname->minor_hash) */ | |
480 | p = &(*p)->rb_right; | |
481 | } | |
482 | ||
483 | rb_link_node(&new_fn->rb_hash, parent, p); | |
484 | rb_insert_color(&new_fn->rb_hash, &info->root); | |
485 | return 0; | |
486 | } | |
487 | ||
488 | ||
489 | ||
490 | /* | |
617ba13b | 491 | * This is a helper function for ext4_dx_readdir. It calls filldir |
ac27a0ec DK |
492 | * for all entres on the fname linked list. (Normally there is only |
493 | * one entry on the linked list, unless there are 62 bit hash collisions.) | |
494 | */ | |
af5bc92d | 495 | static int call_filldir(struct file *filp, void *dirent, |
ac27a0ec DK |
496 | filldir_t filldir, struct fname *fname) |
497 | { | |
498 | struct dir_private_info *info = filp->private_data; | |
499 | loff_t curr_pos; | |
496ad9aa | 500 | struct inode *inode = file_inode(filp); |
af5bc92d | 501 | struct super_block *sb; |
ac27a0ec DK |
502 | int error; |
503 | ||
504 | sb = inode->i_sb; | |
505 | ||
506 | if (!fname) { | |
92b97816 TT |
507 | ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: comm %s: " |
508 | "called with null fname?!?", __func__, __LINE__, | |
509 | inode->i_ino, current->comm); | |
ac27a0ec DK |
510 | return 0; |
511 | } | |
d1f5273e | 512 | curr_pos = hash2pos(filp, fname->hash, fname->minor_hash); |
ac27a0ec DK |
513 | while (fname) { |
514 | error = filldir(dirent, fname->name, | |
515 | fname->name_len, curr_pos, | |
516 | fname->inode, | |
517 | get_dtype(sb, fname->file_type)); | |
518 | if (error) { | |
519 | filp->f_pos = curr_pos; | |
d0156417 | 520 | info->extra_fname = fname; |
ac27a0ec DK |
521 | return error; |
522 | } | |
523 | fname = fname->next; | |
524 | } | |
525 | return 0; | |
526 | } | |
527 | ||
af5bc92d TT |
528 | static int ext4_dx_readdir(struct file *filp, |
529 | void *dirent, filldir_t filldir) | |
ac27a0ec DK |
530 | { |
531 | struct dir_private_info *info = filp->private_data; | |
496ad9aa | 532 | struct inode *inode = file_inode(filp); |
ac27a0ec DK |
533 | struct fname *fname; |
534 | int ret; | |
535 | ||
536 | if (!info) { | |
d1f5273e | 537 | info = ext4_htree_create_dir_info(filp, filp->f_pos); |
ac27a0ec DK |
538 | if (!info) |
539 | return -ENOMEM; | |
540 | filp->private_data = info; | |
541 | } | |
542 | ||
d1f5273e | 543 | if (filp->f_pos == ext4_get_htree_eof(filp)) |
ac27a0ec DK |
544 | return 0; /* EOF */ |
545 | ||
546 | /* Some one has messed with f_pos; reset the world */ | |
547 | if (info->last_pos != filp->f_pos) { | |
548 | free_rb_tree_fname(&info->root); | |
549 | info->curr_node = NULL; | |
550 | info->extra_fname = NULL; | |
d1f5273e FY |
551 | info->curr_hash = pos2maj_hash(filp, filp->f_pos); |
552 | info->curr_minor_hash = pos2min_hash(filp, filp->f_pos); | |
ac27a0ec DK |
553 | } |
554 | ||
555 | /* | |
556 | * If there are any leftover names on the hash collision | |
557 | * chain, return them first. | |
558 | */ | |
d0156417 TT |
559 | if (info->extra_fname) { |
560 | if (call_filldir(filp, dirent, filldir, info->extra_fname)) | |
561 | goto finished; | |
d0156417 | 562 | info->extra_fname = NULL; |
3c37fc86 | 563 | goto next_node; |
d0156417 | 564 | } else if (!info->curr_node) |
ac27a0ec DK |
565 | info->curr_node = rb_first(&info->root); |
566 | ||
567 | while (1) { | |
568 | /* | |
569 | * Fill the rbtree if we have no more entries, | |
570 | * or the inode has changed since we last read in the | |
571 | * cached entries. | |
572 | */ | |
573 | if ((!info->curr_node) || | |
574 | (filp->f_version != inode->i_version)) { | |
575 | info->curr_node = NULL; | |
576 | free_rb_tree_fname(&info->root); | |
577 | filp->f_version = inode->i_version; | |
617ba13b | 578 | ret = ext4_htree_fill_tree(filp, info->curr_hash, |
ac27a0ec DK |
579 | info->curr_minor_hash, |
580 | &info->next_hash); | |
581 | if (ret < 0) | |
582 | return ret; | |
583 | if (ret == 0) { | |
d1f5273e | 584 | filp->f_pos = ext4_get_htree_eof(filp); |
ac27a0ec DK |
585 | break; |
586 | } | |
587 | info->curr_node = rb_first(&info->root); | |
588 | } | |
589 | ||
590 | fname = rb_entry(info->curr_node, struct fname, rb_hash); | |
591 | info->curr_hash = fname->hash; | |
592 | info->curr_minor_hash = fname->minor_hash; | |
593 | if (call_filldir(filp, dirent, filldir, fname)) | |
594 | break; | |
3c37fc86 | 595 | next_node: |
ac27a0ec | 596 | info->curr_node = rb_next(info->curr_node); |
3c37fc86 TT |
597 | if (info->curr_node) { |
598 | fname = rb_entry(info->curr_node, struct fname, | |
599 | rb_hash); | |
600 | info->curr_hash = fname->hash; | |
601 | info->curr_minor_hash = fname->minor_hash; | |
602 | } else { | |
ac27a0ec | 603 | if (info->next_hash == ~0) { |
d1f5273e | 604 | filp->f_pos = ext4_get_htree_eof(filp); |
ac27a0ec DK |
605 | break; |
606 | } | |
607 | info->curr_hash = info->next_hash; | |
608 | info->curr_minor_hash = 0; | |
609 | } | |
610 | } | |
611 | finished: | |
612 | info->last_pos = filp->f_pos; | |
613 | return 0; | |
614 | } | |
615 | ||
af5bc92d | 616 | static int ext4_release_dir(struct inode *inode, struct file *filp) |
ac27a0ec | 617 | { |
63f57933 | 618 | if (filp->private_data) |
617ba13b | 619 | ext4_htree_free_dir_info(filp->private_data); |
ac27a0ec DK |
620 | |
621 | return 0; | |
622 | } | |
d1f5273e FY |
623 | |
624 | const struct file_operations ext4_dir_operations = { | |
625 | .llseek = ext4_dir_llseek, | |
626 | .read = generic_read_dir, | |
627 | .readdir = ext4_readdir, | |
628 | .unlocked_ioctl = ext4_ioctl, | |
629 | #ifdef CONFIG_COMPAT | |
630 | .compat_ioctl = ext4_compat_ioctl, | |
631 | #endif | |
632 | .fsync = ext4_sync_file, | |
633 | .release = ext4_release_dir, | |
634 | }; |