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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/fs/ufs/ufs_dir.c | |
4 | * | |
5 | * Copyright (C) 1996 | |
6 | * Adrian Rodriguez (adrian@franklins-tower.rutgers.edu) | |
7 | * Laboratory for Computer Science Research Computing Facility | |
8 | * Rutgers, The State University of New Jersey | |
9 | * | |
10 | * swab support by Francois-Rene Rideau <fare@tunes.org> 19970406 | |
11 | * | |
12 | * 4.4BSD (FreeBSD) support added on February 1st 1998 by | |
13 | * Niels Kristian Bech Jensen <nkbj@image.dk> partially based | |
14 | * on code by Martin von Loewis <martin@mira.isdn.cs.tu-berlin.de>. | |
b71034e5 ED |
15 | * |
16 | * Migration to usage of "page cache" on May 2006 by | |
17 | * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base. | |
1da177e4 LT |
18 | */ |
19 | ||
20 | #include <linux/time.h> | |
21 | #include <linux/fs.h> | |
82b9d1d0 | 22 | #include <linux/swap.h> |
1da177e4 | 23 | |
e5420598 | 24 | #include "ufs_fs.h" |
bcd6d4ec | 25 | #include "ufs.h" |
1da177e4 LT |
26 | #include "swab.h" |
27 | #include "util.h" | |
28 | ||
1da177e4 LT |
29 | /* |
30 | * NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure. | |
31 | * | |
32 | * len <= UFS_MAXNAMLEN and de != NULL are guaranteed by caller. | |
33 | */ | |
34 | static inline int ufs_match(struct super_block *sb, int len, | |
89031bc7 | 35 | const unsigned char *name, struct ufs_dir_entry *de) |
1da177e4 LT |
36 | { |
37 | if (len != ufs_get_de_namlen(sb, de)) | |
38 | return 0; | |
39 | if (!de->d_ino) | |
40 | return 0; | |
41 | return !memcmp(name, de->d_name, len); | |
42 | } | |
43 | ||
82b9d1d0 | 44 | static int ufs_commit_chunk(struct page *page, loff_t pos, unsigned len) |
1da177e4 | 45 | { |
82b9d1d0 NP |
46 | struct address_space *mapping = page->mapping; |
47 | struct inode *dir = mapping->host; | |
b71034e5 | 48 | int err = 0; |
82b9d1d0 | 49 | |
b71034e5 | 50 | dir->i_version++; |
82b9d1d0 NP |
51 | block_write_end(NULL, mapping, pos, len, len, page, NULL); |
52 | if (pos+len > dir->i_size) { | |
53 | i_size_write(dir, pos+len); | |
54 | mark_inode_dirty(dir); | |
55 | } | |
b71034e5 | 56 | if (IS_DIRSYNC(dir)) |
2b69c828 | 57 | err = write_one_page(page); |
b71034e5 ED |
58 | else |
59 | unlock_page(page); | |
60 | return err; | |
61 | } | |
1da177e4 | 62 | |
b71034e5 ED |
63 | static inline void ufs_put_page(struct page *page) |
64 | { | |
65 | kunmap(page); | |
09cbfeaf | 66 | put_page(page); |
b71034e5 | 67 | } |
1da177e4 | 68 | |
89031bc7 | 69 | ino_t ufs_inode_by_name(struct inode *dir, const struct qstr *qstr) |
b71034e5 ED |
70 | { |
71 | ino_t res = 0; | |
72 | struct ufs_dir_entry *de; | |
73 | struct page *page; | |
74 | ||
08049707 | 75 | de = ufs_find_entry(dir, qstr, &page); |
b71034e5 ED |
76 | if (de) { |
77 | res = fs32_to_cpu(dir->i_sb, de->d_ino); | |
78 | ufs_put_page(page); | |
1da177e4 | 79 | } |
b71034e5 | 80 | return res; |
1da177e4 LT |
81 | } |
82 | ||
1da177e4 | 83 | |
b71034e5 ED |
84 | /* Releases the page */ |
85 | void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de, | |
70d45cdb AV |
86 | struct page *page, struct inode *inode, |
87 | bool update_times) | |
1da177e4 | 88 | { |
82b9d1d0 NP |
89 | loff_t pos = page_offset(page) + |
90 | (char *) de - (char *) page_address(page); | |
91 | unsigned len = fs16_to_cpu(dir->i_sb, de->d_reclen); | |
b71034e5 | 92 | int err; |
1da177e4 | 93 | |
b71034e5 | 94 | lock_page(page); |
f4e420dc | 95 | err = ufs_prepare_chunk(page, pos, len); |
b71034e5 | 96 | BUG_ON(err); |
82b9d1d0 | 97 | |
b71034e5 ED |
98 | de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino); |
99 | ufs_set_de_type(dir->i_sb, de, inode->i_mode); | |
82b9d1d0 NP |
100 | |
101 | err = ufs_commit_chunk(page, pos, len); | |
b71034e5 | 102 | ufs_put_page(page); |
70d45cdb | 103 | if (update_times) |
02027d42 | 104 | dir->i_mtime = dir->i_ctime = current_time(dir); |
b71034e5 ED |
105 | mark_inode_dirty(dir); |
106 | } | |
1da177e4 | 107 | |
1da177e4 | 108 | |
be5b82db | 109 | static bool ufs_check_page(struct page *page) |
b71034e5 ED |
110 | { |
111 | struct inode *dir = page->mapping->host; | |
112 | struct super_block *sb = dir->i_sb; | |
113 | char *kaddr = page_address(page); | |
114 | unsigned offs, rec_len; | |
09cbfeaf | 115 | unsigned limit = PAGE_SIZE; |
f336953b | 116 | const unsigned chunk_mask = UFS_SB(sb)->s_uspi->s_dirblksize - 1; |
b71034e5 ED |
117 | struct ufs_dir_entry *p; |
118 | char *error; | |
119 | ||
09cbfeaf KS |
120 | if ((dir->i_size >> PAGE_SHIFT) == page->index) { |
121 | limit = dir->i_size & ~PAGE_MASK; | |
f336953b | 122 | if (limit & chunk_mask) |
b71034e5 ED |
123 | goto Ebadsize; |
124 | if (!limit) | |
125 | goto out; | |
1da177e4 | 126 | } |
b71034e5 ED |
127 | for (offs = 0; offs <= limit - UFS_DIR_REC_LEN(1); offs += rec_len) { |
128 | p = (struct ufs_dir_entry *)(kaddr + offs); | |
129 | rec_len = fs16_to_cpu(sb, p->d_reclen); | |
130 | ||
131 | if (rec_len < UFS_DIR_REC_LEN(1)) | |
132 | goto Eshort; | |
133 | if (rec_len & 3) | |
134 | goto Ealign; | |
135 | if (rec_len < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, p))) | |
136 | goto Enamelen; | |
f336953b | 137 | if (((offs + rec_len - 1) ^ offs) & ~chunk_mask) |
b71034e5 ED |
138 | goto Espan; |
139 | if (fs32_to_cpu(sb, p->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg * | |
140 | UFS_SB(sb)->s_uspi->s_ncg)) | |
141 | goto Einumber; | |
142 | } | |
143 | if (offs != limit) | |
144 | goto Eend; | |
145 | out: | |
146 | SetPageChecked(page); | |
be5b82db | 147 | return true; |
b71034e5 ED |
148 | |
149 | /* Too bad, we had an error */ | |
150 | ||
151 | Ebadsize: | |
152 | ufs_error(sb, "ufs_check_page", | |
153 | "size of directory #%lu is not a multiple of chunk size", | |
154 | dir->i_ino | |
155 | ); | |
156 | goto fail; | |
157 | Eshort: | |
158 | error = "rec_len is smaller than minimal"; | |
159 | goto bad_entry; | |
160 | Ealign: | |
161 | error = "unaligned directory entry"; | |
162 | goto bad_entry; | |
163 | Enamelen: | |
164 | error = "rec_len is too small for name_len"; | |
165 | goto bad_entry; | |
166 | Espan: | |
167 | error = "directory entry across blocks"; | |
168 | goto bad_entry; | |
169 | Einumber: | |
170 | error = "inode out of bounds"; | |
171 | bad_entry: | |
172 | ufs_error (sb, "ufs_check_page", "bad entry in directory #%lu: %s - " | |
173 | "offset=%lu, rec_len=%d, name_len=%d", | |
09cbfeaf | 174 | dir->i_ino, error, (page->index<<PAGE_SHIFT)+offs, |
b71034e5 ED |
175 | rec_len, ufs_get_de_namlen(sb, p)); |
176 | goto fail; | |
177 | Eend: | |
178 | p = (struct ufs_dir_entry *)(kaddr + offs); | |
9746077a | 179 | ufs_error(sb, __func__, |
b71034e5 ED |
180 | "entry in directory #%lu spans the page boundary" |
181 | "offset=%lu", | |
09cbfeaf | 182 | dir->i_ino, (page->index<<PAGE_SHIFT)+offs); |
b71034e5 | 183 | fail: |
b71034e5 | 184 | SetPageError(page); |
be5b82db | 185 | return false; |
b71034e5 | 186 | } |
1da177e4 | 187 | |
b71034e5 ED |
188 | static struct page *ufs_get_page(struct inode *dir, unsigned long n) |
189 | { | |
190 | struct address_space *mapping = dir->i_mapping; | |
6fe6900e | 191 | struct page *page = read_mapping_page(mapping, n, NULL); |
b71034e5 | 192 | if (!IS_ERR(page)) { |
b71034e5 | 193 | kmap(page); |
be5b82db AV |
194 | if (unlikely(!PageChecked(page))) { |
195 | if (PageError(page) || !ufs_check_page(page)) | |
196 | goto fail; | |
197 | } | |
1da177e4 | 198 | } |
b71034e5 | 199 | return page; |
1da177e4 | 200 | |
b71034e5 ED |
201 | fail: |
202 | ufs_put_page(page); | |
203 | return ERR_PTR(-EIO); | |
1da177e4 LT |
204 | } |
205 | ||
b71034e5 ED |
206 | /* |
207 | * Return the offset into page `page_nr' of the last valid | |
208 | * byte in that page, plus one. | |
209 | */ | |
210 | static unsigned | |
211 | ufs_last_byte(struct inode *inode, unsigned long page_nr) | |
1da177e4 | 212 | { |
b71034e5 ED |
213 | unsigned last_byte = inode->i_size; |
214 | ||
09cbfeaf KS |
215 | last_byte -= page_nr << PAGE_SHIFT; |
216 | if (last_byte > PAGE_SIZE) | |
217 | last_byte = PAGE_SIZE; | |
b71034e5 | 218 | return last_byte; |
1da177e4 LT |
219 | } |
220 | ||
b71034e5 ED |
221 | static inline struct ufs_dir_entry * |
222 | ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p) | |
1da177e4 | 223 | { |
b71034e5 ED |
224 | return (struct ufs_dir_entry *)((char *)p + |
225 | fs16_to_cpu(sb, p->d_reclen)); | |
1da177e4 | 226 | } |
b71034e5 ED |
227 | |
228 | struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p) | |
1da177e4 | 229 | { |
b71034e5 ED |
230 | struct page *page = ufs_get_page(dir, 0); |
231 | struct ufs_dir_entry *de = NULL; | |
1da177e4 | 232 | |
b71034e5 ED |
233 | if (!IS_ERR(page)) { |
234 | de = ufs_next_entry(dir->i_sb, | |
235 | (struct ufs_dir_entry *)page_address(page)); | |
236 | *p = page; | |
1da177e4 | 237 | } |
b71034e5 | 238 | return de; |
1da177e4 LT |
239 | } |
240 | ||
b71034e5 ED |
241 | /* |
242 | * ufs_find_entry() | |
243 | * | |
244 | * finds an entry in the specified directory with the wanted name. It | |
245 | * returns the page in which the entry was found, and the entry itself | |
246 | * (as a parameter - res_dir). Page is returned mapped and unlocked. | |
247 | * Entry is guaranteed to be valid. | |
248 | */ | |
89031bc7 | 249 | struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr, |
b71034e5 | 250 | struct page **res_page) |
1da177e4 | 251 | { |
b71034e5 | 252 | struct super_block *sb = dir->i_sb; |
89031bc7 | 253 | const unsigned char *name = qstr->name; |
08049707 | 254 | int namelen = qstr->len; |
b71034e5 ED |
255 | unsigned reclen = UFS_DIR_REC_LEN(namelen); |
256 | unsigned long start, n; | |
5d754ced | 257 | unsigned long npages = dir_pages(dir); |
b71034e5 | 258 | struct page *page = NULL; |
dd187a26 | 259 | struct ufs_inode_info *ui = UFS_I(dir); |
b71034e5 ED |
260 | struct ufs_dir_entry *de; |
261 | ||
abf5d15f | 262 | UFSD("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen); |
b71034e5 ED |
263 | |
264 | if (npages == 0 || namelen > UFS_MAXNAMLEN) | |
265 | goto out; | |
266 | ||
267 | /* OFFSET_CACHE */ | |
268 | *res_page = NULL; | |
269 | ||
dd187a26 ED |
270 | start = ui->i_dir_start_lookup; |
271 | ||
b71034e5 ED |
272 | if (start >= npages) |
273 | start = 0; | |
274 | n = start; | |
275 | do { | |
276 | char *kaddr; | |
277 | page = ufs_get_page(dir, n); | |
278 | if (!IS_ERR(page)) { | |
279 | kaddr = page_address(page); | |
280 | de = (struct ufs_dir_entry *) kaddr; | |
281 | kaddr += ufs_last_byte(dir, n) - reclen; | |
282 | while ((char *) de <= kaddr) { | |
b71034e5 ED |
283 | if (ufs_match(sb, namelen, name, de)) |
284 | goto found; | |
285 | de = ufs_next_entry(sb, de); | |
286 | } | |
287 | ufs_put_page(page); | |
288 | } | |
289 | if (++n >= npages) | |
290 | n = 0; | |
291 | } while (n != start); | |
292 | out: | |
293 | return NULL; | |
294 | ||
295 | found: | |
296 | *res_page = page; | |
dd187a26 | 297 | ui->i_dir_start_lookup = n; |
b71034e5 | 298 | return de; |
1da177e4 LT |
299 | } |
300 | ||
301 | /* | |
b71034e5 | 302 | * Parent is locked. |
1da177e4 LT |
303 | */ |
304 | int ufs_add_link(struct dentry *dentry, struct inode *inode) | |
305 | { | |
2b0143b5 | 306 | struct inode *dir = d_inode(dentry->d_parent); |
89031bc7 | 307 | const unsigned char *name = dentry->d_name.name; |
1da177e4 | 308 | int namelen = dentry->d_name.len; |
b71034e5 ED |
309 | struct super_block *sb = dir->i_sb; |
310 | unsigned reclen = UFS_DIR_REC_LEN(namelen); | |
f336953b | 311 | const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize; |
b71034e5 ED |
312 | unsigned short rec_len, name_len; |
313 | struct page *page = NULL; | |
314 | struct ufs_dir_entry *de; | |
5d754ced | 315 | unsigned long npages = dir_pages(dir); |
b71034e5 ED |
316 | unsigned long n; |
317 | char *kaddr; | |
82b9d1d0 | 318 | loff_t pos; |
1da177e4 LT |
319 | int err; |
320 | ||
abf5d15f | 321 | UFSD("ENTER, name %s, namelen %u\n", name, namelen); |
b71034e5 ED |
322 | |
323 | /* | |
324 | * We take care of directory expansion in the same loop. | |
325 | * This code plays outside i_size, so it locks the page | |
326 | * to protect that region. | |
327 | */ | |
328 | for (n = 0; n <= npages; n++) { | |
329 | char *dir_end; | |
330 | ||
331 | page = ufs_get_page(dir, n); | |
332 | err = PTR_ERR(page); | |
333 | if (IS_ERR(page)) | |
334 | goto out; | |
335 | lock_page(page); | |
336 | kaddr = page_address(page); | |
337 | dir_end = kaddr + ufs_last_byte(dir, n); | |
338 | de = (struct ufs_dir_entry *)kaddr; | |
09cbfeaf | 339 | kaddr += PAGE_SIZE - reclen; |
b71034e5 ED |
340 | while ((char *)de <= kaddr) { |
341 | if ((char *)de == dir_end) { | |
342 | /* We hit i_size */ | |
343 | name_len = 0; | |
f336953b ED |
344 | rec_len = chunk_size; |
345 | de->d_reclen = cpu_to_fs16(sb, chunk_size); | |
b71034e5 ED |
346 | de->d_ino = 0; |
347 | goto got_it; | |
1da177e4 | 348 | } |
b71034e5 | 349 | if (de->d_reclen == 0) { |
9746077a | 350 | ufs_error(dir->i_sb, __func__, |
b71034e5 ED |
351 | "zero-length directory entry"); |
352 | err = -EIO; | |
353 | goto out_unlock; | |
354 | } | |
355 | err = -EEXIST; | |
356 | if (ufs_match(sb, namelen, name, de)) | |
357 | goto out_unlock; | |
358 | name_len = UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)); | |
359 | rec_len = fs16_to_cpu(sb, de->d_reclen); | |
360 | if (!de->d_ino && rec_len >= reclen) | |
361 | goto got_it; | |
362 | if (rec_len >= name_len + reclen) | |
363 | goto got_it; | |
364 | de = (struct ufs_dir_entry *) ((char *) de + rec_len); | |
1da177e4 | 365 | } |
b71034e5 ED |
366 | unlock_page(page); |
367 | ufs_put_page(page); | |
1da177e4 | 368 | } |
b71034e5 ED |
369 | BUG(); |
370 | return -EINVAL; | |
371 | ||
372 | got_it: | |
82b9d1d0 NP |
373 | pos = page_offset(page) + |
374 | (char*)de - (char*)page_address(page); | |
f4e420dc | 375 | err = ufs_prepare_chunk(page, pos, rec_len); |
b71034e5 ED |
376 | if (err) |
377 | goto out_unlock; | |
1da177e4 | 378 | if (de->d_ino) { |
b71034e5 ED |
379 | struct ufs_dir_entry *de1 = |
380 | (struct ufs_dir_entry *) ((char *) de + name_len); | |
381 | de1->d_reclen = cpu_to_fs16(sb, rec_len - name_len); | |
382 | de->d_reclen = cpu_to_fs16(sb, name_len); | |
383 | ||
1da177e4 LT |
384 | de = de1; |
385 | } | |
b71034e5 | 386 | |
1da177e4 | 387 | ufs_set_de_namlen(sb, de, namelen); |
b71034e5 | 388 | memcpy(de->d_name, name, namelen + 1); |
1da177e4 LT |
389 | de->d_ino = cpu_to_fs32(sb, inode->i_ino); |
390 | ufs_set_de_type(sb, de, inode->i_mode); | |
b71034e5 | 391 | |
82b9d1d0 | 392 | err = ufs_commit_chunk(page, pos, rec_len); |
02027d42 | 393 | dir->i_mtime = dir->i_ctime = current_time(dir); |
b71034e5 | 394 | |
1da177e4 | 395 | mark_inode_dirty(dir); |
b71034e5 ED |
396 | /* OFFSET_CACHE */ |
397 | out_put: | |
398 | ufs_put_page(page); | |
399 | out: | |
400 | return err; | |
401 | out_unlock: | |
402 | unlock_page(page); | |
403 | goto out_put; | |
404 | } | |
405 | ||
406 | static inline unsigned | |
407 | ufs_validate_entry(struct super_block *sb, char *base, | |
408 | unsigned offset, unsigned mask) | |
409 | { | |
410 | struct ufs_dir_entry *de = (struct ufs_dir_entry*)(base + offset); | |
411 | struct ufs_dir_entry *p = (struct ufs_dir_entry*)(base + (offset&mask)); | |
e0d508f1 | 412 | while ((char*)p < (char*)de) |
b71034e5 | 413 | p = ufs_next_entry(sb, p); |
b71034e5 ED |
414 | return (char *)p - base; |
415 | } | |
1da177e4 | 416 | |
b71034e5 ED |
417 | |
418 | /* | |
419 | * This is blatantly stolen from ext2fs | |
420 | */ | |
421 | static int | |
80886298 | 422 | ufs_readdir(struct file *file, struct dir_context *ctx) |
b71034e5 | 423 | { |
80886298 AV |
424 | loff_t pos = ctx->pos; |
425 | struct inode *inode = file_inode(file); | |
b71034e5 | 426 | struct super_block *sb = inode->i_sb; |
09cbfeaf KS |
427 | unsigned int offset = pos & ~PAGE_MASK; |
428 | unsigned long n = pos >> PAGE_SHIFT; | |
5d754ced | 429 | unsigned long npages = dir_pages(inode); |
f336953b | 430 | unsigned chunk_mask = ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); |
80886298 | 431 | int need_revalidate = file->f_version != inode->i_version; |
b71034e5 ED |
432 | unsigned flags = UFS_SB(sb)->s_flags; |
433 | ||
abf5d15f | 434 | UFSD("BEGIN\n"); |
b71034e5 ED |
435 | |
436 | if (pos > inode->i_size - UFS_DIR_REC_LEN(1)) | |
437 | return 0; | |
438 | ||
439 | for ( ; n < npages; n++, offset = 0) { | |
440 | char *kaddr, *limit; | |
441 | struct ufs_dir_entry *de; | |
442 | ||
443 | struct page *page = ufs_get_page(inode, n); | |
444 | ||
445 | if (IS_ERR(page)) { | |
9746077a | 446 | ufs_error(sb, __func__, |
b71034e5 ED |
447 | "bad page in #%lu", |
448 | inode->i_ino); | |
09cbfeaf | 449 | ctx->pos += PAGE_SIZE - offset; |
b71034e5 ED |
450 | return -EIO; |
451 | } | |
452 | kaddr = page_address(page); | |
453 | if (unlikely(need_revalidate)) { | |
454 | if (offset) { | |
455 | offset = ufs_validate_entry(sb, kaddr, offset, chunk_mask); | |
09cbfeaf | 456 | ctx->pos = (n<<PAGE_SHIFT) + offset; |
b71034e5 | 457 | } |
80886298 | 458 | file->f_version = inode->i_version; |
b71034e5 ED |
459 | need_revalidate = 0; |
460 | } | |
461 | de = (struct ufs_dir_entry *)(kaddr+offset); | |
462 | limit = kaddr + ufs_last_byte(inode, n) - UFS_DIR_REC_LEN(1); | |
463 | for ( ;(char*)de <= limit; de = ufs_next_entry(sb, de)) { | |
b71034e5 | 464 | if (de->d_ino) { |
b71034e5 ED |
465 | unsigned char d_type = DT_UNKNOWN; |
466 | ||
abf5d15f ED |
467 | UFSD("filldir(%s,%u)\n", de->d_name, |
468 | fs32_to_cpu(sb, de->d_ino)); | |
469 | UFSD("namlen %u\n", ufs_get_de_namlen(sb, de)); | |
b71034e5 ED |
470 | |
471 | if ((flags & UFS_DE_MASK) == UFS_DE_44BSD) | |
472 | d_type = de->d_u.d_44.d_type; | |
473 | ||
80886298 | 474 | if (!dir_emit(ctx, de->d_name, |
b71034e5 | 475 | ufs_get_de_namlen(sb, de), |
80886298 AV |
476 | fs32_to_cpu(sb, de->d_ino), |
477 | d_type)) { | |
b71034e5 ED |
478 | ufs_put_page(page); |
479 | return 0; | |
480 | } | |
481 | } | |
80886298 | 482 | ctx->pos += fs16_to_cpu(sb, de->d_reclen); |
b71034e5 ED |
483 | } |
484 | ufs_put_page(page); | |
485 | } | |
1da177e4 LT |
486 | return 0; |
487 | } | |
488 | ||
b71034e5 | 489 | |
1da177e4 LT |
490 | /* |
491 | * ufs_delete_entry deletes a directory entry by merging it with the | |
492 | * previous entry. | |
493 | */ | |
b71034e5 ED |
494 | int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir, |
495 | struct page * page) | |
1da177e4 | 496 | { |
b71034e5 | 497 | struct super_block *sb = inode->i_sb; |
b71034e5 | 498 | char *kaddr = page_address(page); |
f336953b | 499 | unsigned from = ((char*)dir - kaddr) & ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); |
b71034e5 | 500 | unsigned to = ((char*)dir - kaddr) + fs16_to_cpu(sb, dir->d_reclen); |
82b9d1d0 | 501 | loff_t pos; |
b71034e5 ED |
502 | struct ufs_dir_entry *pde = NULL; |
503 | struct ufs_dir_entry *de = (struct ufs_dir_entry *) (kaddr + from); | |
504 | int err; | |
1da177e4 | 505 | |
abf5d15f | 506 | UFSD("ENTER\n"); |
1da177e4 | 507 | |
abf5d15f | 508 | UFSD("ino %u, reclen %u, namlen %u, name %s\n", |
b71034e5 ED |
509 | fs32_to_cpu(sb, de->d_ino), |
510 | fs16_to_cpu(sb, de->d_reclen), | |
abf5d15f | 511 | ufs_get_de_namlen(sb, de), de->d_name); |
b71034e5 ED |
512 | |
513 | while ((char*)de < (char*)dir) { | |
514 | if (de->d_reclen == 0) { | |
9746077a | 515 | ufs_error(inode->i_sb, __func__, |
b71034e5 ED |
516 | "zero-length directory entry"); |
517 | err = -EIO; | |
518 | goto out; | |
1da177e4 | 519 | } |
b71034e5 ED |
520 | pde = de; |
521 | de = ufs_next_entry(sb, de); | |
1da177e4 | 522 | } |
b71034e5 ED |
523 | if (pde) |
524 | from = (char*)pde - (char*)page_address(page); | |
82b9d1d0 NP |
525 | |
526 | pos = page_offset(page) + from; | |
b71034e5 | 527 | lock_page(page); |
f4e420dc | 528 | err = ufs_prepare_chunk(page, pos, to - from); |
b71034e5 ED |
529 | BUG_ON(err); |
530 | if (pde) | |
82b9d1d0 | 531 | pde->d_reclen = cpu_to_fs16(sb, to - from); |
b71034e5 | 532 | dir->d_ino = 0; |
82b9d1d0 | 533 | err = ufs_commit_chunk(page, pos, to - from); |
02027d42 | 534 | inode->i_ctime = inode->i_mtime = current_time(inode); |
b71034e5 ED |
535 | mark_inode_dirty(inode); |
536 | out: | |
537 | ufs_put_page(page); | |
abf5d15f | 538 | UFSD("EXIT\n"); |
b71034e5 | 539 | return err; |
1da177e4 LT |
540 | } |
541 | ||
542 | int ufs_make_empty(struct inode * inode, struct inode *dir) | |
543 | { | |
544 | struct super_block * sb = dir->i_sb; | |
b71034e5 ED |
545 | struct address_space *mapping = inode->i_mapping; |
546 | struct page *page = grab_cache_page(mapping, 0); | |
f336953b | 547 | const unsigned int chunk_size = UFS_SB(sb)->s_uspi->s_dirblksize; |
1da177e4 | 548 | struct ufs_dir_entry * de; |
b71034e5 | 549 | char *base; |
1da177e4 LT |
550 | int err; |
551 | ||
b71034e5 ED |
552 | if (!page) |
553 | return -ENOMEM; | |
82b9d1d0 | 554 | |
f4e420dc | 555 | err = ufs_prepare_chunk(page, 0, chunk_size); |
b71034e5 ED |
556 | if (err) { |
557 | unlock_page(page); | |
558 | goto fail; | |
559 | } | |
560 | ||
82b9d1d0 | 561 | kmap(page); |
b71034e5 | 562 | base = (char*)page_address(page); |
09cbfeaf | 563 | memset(base, 0, PAGE_SIZE); |
b71034e5 ED |
564 | |
565 | de = (struct ufs_dir_entry *) base; | |
1da177e4 | 566 | |
1da177e4 LT |
567 | de->d_ino = cpu_to_fs32(sb, inode->i_ino); |
568 | ufs_set_de_type(sb, de, inode->i_mode); | |
569 | ufs_set_de_namlen(sb, de, 1); | |
570 | de->d_reclen = cpu_to_fs16(sb, UFS_DIR_REC_LEN(1)); | |
571 | strcpy (de->d_name, "."); | |
572 | de = (struct ufs_dir_entry *) | |
573 | ((char *)de + fs16_to_cpu(sb, de->d_reclen)); | |
574 | de->d_ino = cpu_to_fs32(sb, dir->i_ino); | |
575 | ufs_set_de_type(sb, de, dir->i_mode); | |
f336953b | 576 | de->d_reclen = cpu_to_fs16(sb, chunk_size - UFS_DIR_REC_LEN(1)); |
1da177e4 LT |
577 | ufs_set_de_namlen(sb, de, 2); |
578 | strcpy (de->d_name, ".."); | |
82b9d1d0 | 579 | kunmap(page); |
b71034e5 | 580 | |
f336953b | 581 | err = ufs_commit_chunk(page, 0, chunk_size); |
b71034e5 | 582 | fail: |
09cbfeaf | 583 | put_page(page); |
b71034e5 | 584 | return err; |
1da177e4 LT |
585 | } |
586 | ||
587 | /* | |
588 | * routine to check that the specified directory is empty (for rmdir) | |
589 | */ | |
b71034e5 | 590 | int ufs_empty_dir(struct inode * inode) |
1da177e4 | 591 | { |
b71034e5 ED |
592 | struct super_block *sb = inode->i_sb; |
593 | struct page *page = NULL; | |
5d754ced | 594 | unsigned long i, npages = dir_pages(inode); |
b71034e5 ED |
595 | |
596 | for (i = 0; i < npages; i++) { | |
597 | char *kaddr; | |
598 | struct ufs_dir_entry *de; | |
599 | page = ufs_get_page(inode, i); | |
600 | ||
601 | if (IS_ERR(page)) | |
602 | continue; | |
603 | ||
604 | kaddr = page_address(page); | |
605 | de = (struct ufs_dir_entry *)kaddr; | |
606 | kaddr += ufs_last_byte(inode, i) - UFS_DIR_REC_LEN(1); | |
607 | ||
608 | while ((char *)de <= kaddr) { | |
609 | if (de->d_reclen == 0) { | |
9746077a | 610 | ufs_error(inode->i_sb, __func__, |
b71034e5 ED |
611 | "zero-length directory entry: " |
612 | "kaddr=%p, de=%p\n", kaddr, de); | |
613 | goto not_empty; | |
1da177e4 | 614 | } |
b71034e5 ED |
615 | if (de->d_ino) { |
616 | u16 namelen=ufs_get_de_namlen(sb, de); | |
617 | /* check for . and .. */ | |
618 | if (de->d_name[0] != '.') | |
619 | goto not_empty; | |
620 | if (namelen > 2) | |
621 | goto not_empty; | |
622 | if (namelen < 2) { | |
623 | if (inode->i_ino != | |
624 | fs32_to_cpu(sb, de->d_ino)) | |
625 | goto not_empty; | |
626 | } else if (de->d_name[1] != '.') | |
627 | goto not_empty; | |
628 | } | |
629 | de = ufs_next_entry(sb, de); | |
1da177e4 | 630 | } |
b71034e5 | 631 | ufs_put_page(page); |
1da177e4 | 632 | } |
1da177e4 | 633 | return 1; |
b71034e5 ED |
634 | |
635 | not_empty: | |
636 | ufs_put_page(page); | |
637 | return 0; | |
1da177e4 LT |
638 | } |
639 | ||
4b6f5d20 | 640 | const struct file_operations ufs_dir_operations = { |
1da177e4 | 641 | .read = generic_read_dir, |
3b0a3c1a | 642 | .iterate_shared = ufs_readdir, |
1b061d92 | 643 | .fsync = generic_file_fsync, |
3222a3e5 | 644 | .llseek = generic_file_llseek, |
1da177e4 | 645 | }; |